diff --git a/config/payment.php b/config/payment.php
index 0d980cb..abd0899 100644
--- a/config/payment.php
+++ b/config/payment.php
@@ -41,8 +41,7 @@
         ],
 
         'wave' => [
-            'client_key' => '',
-            'client_secret' => '',
+            'api_key' => '', // Your Wave API key (starts with wave_sn_prod_ or wave_sn_sandbox_)
             'webhook_secret' => ''
         ],
 
diff --git a/src/IvoryCost/OrangeMoney/OrangeMoneyGateway.php b/src/IvoryCost/OrangeMoney/OrangeMoneyGateway.php
index 9c94e53..9f17fd2 100644
--- a/src/IvoryCost/OrangeMoney/OrangeMoneyGateway.php
+++ b/src/IvoryCost/OrangeMoney/OrangeMoneyGateway.php
@@ -37,9 +37,17 @@ public function payment(...$args)
         // Set the right production endpoint
         $payment->setPaymentEndpoint('/orange-money-webpay/v1/webpayment');
 
-        $payment->setNotifyUrl($args['notif_url']);
-        $payment->setCancelUrl($args['cancel_url']);
-        $payment->setReturnUrl($args['return_url']);
+        if (isset($args['notif_url'])) {
+            $payment->setNotifyUrl($args['notif_url']);
+        }
+
+        if (isset($args['cancel_url'])) {
+            $payment->setCancelUrl($args['cancel_url']);
+        }
+
+        if (isset($args['return_url'])) {
+            $payment->setReturnUrl($args['return_url']);
+        }
 
         $amount = $args['amount'];
         $reference = $args['reference'];
diff --git a/src/IvoryCost/Wave/WaveCheckoutSession.php b/src/IvoryCost/Wave/WaveCheckoutSession.php
new file mode 100644
index 0000000..9a9afe2
--- /dev/null
+++ b/src/IvoryCost/Wave/WaveCheckoutSession.php
@@ -0,0 +1,249 @@
+<?php
+
+namespace Bow\Payment\IvoryCost\Wave;
+
+/**
+ * Wave Checkout Session
+ * Represents a Wave checkout session object
+ */
+class WaveCheckoutSession
+{
+    /**
+     * WaveCheckoutSession constructor
+     *
+     * @param string $id
+     * @param string $amount
+     * @param string $checkoutStatus
+     * @param string $paymentStatus
+     * @param string $currency
+     * @param string $businessName
+     * @param string $successUrl
+     * @param string $errorUrl
+     * @param string $waveLaunchUrl
+     * @param string|null $transactionId
+     * @param string|null $clientReference
+     * @param string|null $aggregatedMerchantId
+     * @param string|null $restrictPayerMobile
+     * @param array|null $lastPaymentError
+     * @param string $whenCreated
+     * @param string|null $whenCompleted
+     * @param string $whenExpires
+     */
+    public function __construct(
+        private string $id,
+        private string $amount,
+        private string $checkoutStatus,
+        private string $paymentStatus,
+        private string $currency,
+        private string $businessName,
+        private string $successUrl,
+        private string $errorUrl,
+        private string $waveLaunchUrl,
+        private ?string $transactionId = null,
+        private ?string $clientReference = null,
+        private ?string $aggregatedMerchantId = null,
+        private ?string $restrictPayerMobile = null,
+        private ?array $lastPaymentError = null,
+        private string $whenCreated = '',
+        private ?string $whenCompleted = null,
+        private string $whenExpires = ''
+    ) {
+    }
+
+    /**
+     * Create from API response
+     *
+     * @param array $data
+     * @return self
+     */
+    public static function fromResponse(array $data): self
+    {
+        return new self(
+            id: $data['id'],
+            amount: $data['amount'],
+            checkoutStatus: $data['checkout_status'],
+            paymentStatus: $data['payment_status'],
+            currency: $data['currency'],
+            businessName: $data['business_name'],
+            successUrl: $data['success_url'],
+            errorUrl: $data['error_url'],
+            waveLaunchUrl: $data['wave_launch_url'],
+            transactionId: $data['transaction_id'] ?? null,
+            clientReference: $data['client_reference'] ?? null,
+            aggregatedMerchantId: $data['aggregated_merchant_id'] ?? null,
+            restrictPayerMobile: $data['restrict_payer_mobile'] ?? null,
+            lastPaymentError: $data['last_payment_error'] ?? null,
+            whenCreated: $data['when_created'],
+            whenCompleted: $data['when_completed'] ?? null,
+            whenExpires: $data['when_expires']
+        );
+    }
+
+    /**
+     * Get checkout session ID
+     *
+     * @return string
+     */
+    public function getId(): string
+    {
+        return $this->id;
+    }
+
+    /**
+     * Get amount
+     *
+     * @return string
+     */
+    public function getAmount(): string
+    {
+        return $this->amount;
+    }
+
+    /**
+     * Get checkout status
+     *
+     * @return string
+     */
+    public function getCheckoutStatus(): string
+    {
+        return $this->checkoutStatus;
+    }
+
+    /**
+     * Get payment status
+     *
+     * @return string
+     */
+    public function getPaymentStatus(): string
+    {
+        return $this->paymentStatus;
+    }
+
+    /**
+     * Get Wave launch URL
+     *
+     * @return string
+     */
+    public function getWaveLaunchUrl(): string
+    {
+        return $this->waveLaunchUrl;
+    }
+
+    /**
+     * Get transaction ID
+     *
+     * @return string|null
+     */
+    public function getTransactionId(): ?string
+    {
+        return $this->transactionId;
+    }
+
+    /**
+     * Get client reference
+     *
+     * @return string|null
+     */
+    public function getClientReference(): ?string
+    {
+        return $this->clientReference;
+    }
+
+    /**
+     * Check if checkout is open
+     *
+     * @return bool
+     */
+    public function isOpen(): bool
+    {
+        return $this->checkoutStatus === 'open';
+    }
+
+    /**
+     * Check if checkout is complete
+     *
+     * @return bool
+     */
+    public function isComplete(): bool
+    {
+        return $this->checkoutStatus === 'complete';
+    }
+
+    /**
+     * Check if checkout is expired
+     *
+     * @return bool
+     */
+    public function isExpired(): bool
+    {
+        return $this->checkoutStatus === 'expired';
+    }
+
+    /**
+     * Check if payment succeeded
+     *
+     * @return bool
+     */
+    public function isPaymentSucceeded(): bool
+    {
+        return $this->paymentStatus === 'succeeded';
+    }
+
+    /**
+     * Check if payment is processing
+     *
+     * @return bool
+     */
+    public function isPaymentProcessing(): bool
+    {
+        return $this->paymentStatus === 'processing';
+    }
+
+    /**
+     * Check if payment is cancelled
+     *
+     * @return bool
+     */
+    public function isPaymentCancelled(): bool
+    {
+        return $this->paymentStatus === 'cancelled';
+    }
+
+    /**
+     * Get last payment error
+     *
+     * @return array|null
+     */
+    public function getLastPaymentError(): ?array
+    {
+        return $this->lastPaymentError;
+    }
+
+    /**
+     * Convert to array
+     *
+     * @return array
+     */
+    public function toArray(): array
+    {
+        return [
+            'id' => $this->id,
+            'amount' => $this->amount,
+            'checkout_status' => $this->checkoutStatus,
+            'payment_status' => $this->paymentStatus,
+            'currency' => $this->currency,
+            'business_name' => $this->businessName,
+            'success_url' => $this->successUrl,
+            'error_url' => $this->errorUrl,
+            'wave_launch_url' => $this->waveLaunchUrl,
+            'transaction_id' => $this->transactionId,
+            'client_reference' => $this->clientReference,
+            'aggregated_merchant_id' => $this->aggregatedMerchantId,
+            'restrict_payer_mobile' => $this->restrictPayerMobile,
+            'last_payment_error' => $this->lastPaymentError,
+            'when_created' => $this->whenCreated,
+            'when_completed' => $this->whenCompleted,
+            'when_expires' => $this->whenExpires,
+        ];
+    }
+}
diff --git a/src/IvoryCost/Wave/WaveClient.php b/src/IvoryCost/Wave/WaveClient.php
new file mode 100644
index 0000000..703e2e1
--- /dev/null
+++ b/src/IvoryCost/Wave/WaveClient.php
@@ -0,0 +1,382 @@
+<?php
+
+namespace Bow\Payment\IvoryCost\Wave;
+
+use GuzzleHttp\Client as HttpClient;
+use Bow\Payment\Exceptions\PaymentRequestException;
+
+/**
+ * Wave API Client
+ * Handles communication with Wave Checkout API
+ */
+class WaveClient
+{
+    /**
+     * Base URL for Wave API
+     */
+    private const BASE_URL = 'https://api.wave.com';
+
+    /**
+     * HTTP client instance
+     *
+     * @var HttpClient
+     */
+    private HttpClient $http;
+
+    /**
+     * API Key
+     *
+     * @var string
+     */
+    private string $apiKey;
+
+    /**
+     * WaveClient constructor
+     *
+     * @param string $apiKey
+     */
+    public function __construct(string $apiKey)
+    {
+        $this->apiKey = $apiKey;
+        $this->http = new HttpClient([
+            'base_uri' => self::BASE_URL,
+            'headers' => [
+                'Authorization' => 'Bearer ' . $apiKey,
+                'Content-Type' => 'application/json',
+                'Accept' => 'application/json',
+            ],
+        ]);
+    }
+
+    /**
+     * Create a checkout session
+     *
+     * @param array $data
+     * @param string|null $idempotencyKey Unique key to prevent duplicate payments
+     * @return WaveCheckoutSession
+     * @throws PaymentRequestException
+     */
+    public function createCheckoutSession(array $data, ?string $idempotencyKey = null): WaveCheckoutSession
+    {
+        try {
+            $headers = [];
+            if ($idempotencyKey !== null) {
+                $headers['Idempotency-Key'] = $idempotencyKey;
+            }
+
+            $response = $this->http->post('/v1/checkout/sessions', [
+                'json' => $this->buildCheckoutPayload($data),
+                'headers' => $headers,
+            ]);
+
+            $content = $response->getBody()->getContents();
+            $sessionData = json_decode($content, true);
+
+            if (json_last_error() !== JSON_ERROR_NONE) {
+                throw new PaymentRequestException('Invalid JSON response from Wave API');
+            }
+
+            return WaveCheckoutSession::fromResponse($sessionData);
+        } catch (\GuzzleHttp\Exception\ClientException $e) {
+            return $this->handleClientException($e);
+        } catch (\GuzzleHttp\Exception\ServerException $e) {
+            throw new PaymentRequestException(
+                'Wave API server error: ' . $e->getMessage(),
+                $e->getCode(),
+                $e
+            );
+        } catch (\Exception $e) {
+            throw new PaymentRequestException(
+                'Failed to create Wave checkout session: ' . $e->getMessage(),
+                0,
+                $e
+            );
+        }
+    }
+
+    /**
+     * Retrieve a checkout session by ID
+     *
+     * @param string $sessionId
+     * @return WaveCheckoutSession
+     * @throws PaymentRequestException
+     */
+    public function retrieveCheckoutSession(string $sessionId): WaveCheckoutSession
+    {
+        try {
+            $response = $this->http->get("/v1/checkout/sessions/{$sessionId}");
+
+            $content = $response->getBody()->getContents();
+            $sessionData = json_decode($content, true);
+
+            if (json_last_error() !== JSON_ERROR_NONE) {
+                throw new PaymentRequestException('Invalid JSON response from Wave API');
+            }
+
+            return WaveCheckoutSession::fromResponse($sessionData);
+        } catch (\GuzzleHttp\Exception\ClientException $e) {
+            return $this->handleClientException($e);
+        } catch (\GuzzleHttp\Exception\ServerException $e) {
+            throw new PaymentRequestException(
+                'Wave API server error: ' . $e->getMessage(),
+                $e->getCode(),
+                $e
+            );
+        } catch (\Exception $e) {
+            throw new PaymentRequestException(
+                'Failed to retrieve Wave checkout session: ' . $e->getMessage(),
+                0,
+                $e
+            );
+        }
+    }
+
+    /**
+     * Retrieve a checkout session by transaction ID
+     *
+     * @param string $transactionId
+     * @return WaveCheckoutSession
+     * @throws PaymentRequestException
+     */
+    public function retrieveCheckoutByTransactionId(string $transactionId): WaveCheckoutSession
+    {
+        try {
+            $response = $this->http->get('/v1/checkout/sessions', [
+                'query' => ['transaction_id' => $transactionId],
+            ]);
+
+            $content = $response->getBody()->getContents();
+            $sessionData = json_decode($content, true);
+
+            if (json_last_error() !== JSON_ERROR_NONE) {
+                throw new PaymentRequestException('Invalid JSON response from Wave API');
+            }
+
+            return WaveCheckoutSession::fromResponse($sessionData);
+        } catch (\GuzzleHttp\Exception\ClientException $e) {
+            return $this->handleClientException($e);
+        } catch (\GuzzleHttp\Exception\ServerException $e) {
+            throw new PaymentRequestException(
+                'Wave API server error: ' . $e->getMessage(),
+                $e->getCode(),
+                $e
+            );
+        } catch (\Exception $e) {
+            throw new PaymentRequestException(
+                'Failed to retrieve Wave checkout session: ' . $e->getMessage(),
+                0,
+                $e
+            );
+        }
+    }
+
+    /**
+     * Search for checkout sessions by client reference
+     *
+     * @param string $clientReference
+     * @return array
+     * @throws PaymentRequestException
+     */
+    public function searchCheckoutSessions(string $clientReference): array
+    {
+        try {
+            $response = $this->http->get('/v1/checkout/sessions/search', [
+                'query' => ['client_reference' => $clientReference],
+            ]);
+
+            $content = $response->getBody()->getContents();
+            $data = json_decode($content, true);
+
+            if (json_last_error() !== JSON_ERROR_NONE) {
+                throw new PaymentRequestException('Invalid JSON response from Wave API');
+            }
+
+            $sessions = [];
+            foreach ($data['result'] ?? [] as $sessionData) {
+                $sessions[] = WaveCheckoutSession::fromResponse($sessionData);
+            }
+
+            return $sessions;
+        } catch (\GuzzleHttp\Exception\ClientException $e) {
+            return $this->handleClientException($e);
+        } catch (\GuzzleHttp\Exception\ServerException $e) {
+            throw new PaymentRequestException(
+                'Wave API server error: ' . $e->getMessage(),
+                $e->getCode(),
+                $e
+            );
+        } catch (\Exception $e) {
+            throw new PaymentRequestException(
+                'Failed to search Wave checkout sessions: ' . $e->getMessage(),
+                0,
+                $e
+            );
+        }
+    }
+
+    /**
+     * Refund a checkout session
+     *
+     * @param string $sessionId
+     * @return bool
+     * @throws PaymentRequestException
+     */
+    public function refundCheckoutSession(string $sessionId): bool
+    {
+        try {
+            $response = $this->http->post("/v1/checkout/sessions/{$sessionId}/refund");
+            return $response->getStatusCode() === 200;
+        } catch (\GuzzleHttp\Exception\ClientException $e) {
+            return $this->handleClientException($e);
+        } catch (\GuzzleHttp\Exception\ServerException $e) {
+            throw new PaymentRequestException(
+                'Wave API server error: ' . $e->getMessage(),
+                $e->getCode(),
+                $e
+            );
+        } catch (\Exception $e) {
+            throw new PaymentRequestException(
+                'Failed to refund Wave checkout session: ' . $e->getMessage(),
+                0,
+                $e
+            );
+        }
+    }
+
+    /**
+     * Expire a checkout session
+     *
+     * @param string $sessionId
+     * @return bool
+     * @throws PaymentRequestException
+     */
+    public function expireCheckoutSession(string $sessionId): bool
+    {
+        try {
+            $response = $this->http->post("/v1/checkout/sessions/{$sessionId}/expire");
+            return $response->getStatusCode() === 200;
+        } catch (\GuzzleHttp\Exception\ClientException $e) {
+            return $this->handleClientException($e);
+        } catch (\GuzzleHttp\Exception\ServerException $e) {
+            throw new PaymentRequestException(
+                'Wave API server error: ' . $e->getMessage(),
+                $e->getCode(),
+                $e
+            );
+        } catch (\Exception $e) {
+            throw new PaymentRequestException(
+                'Failed to expire Wave checkout session: ' . $e->getMessage(),
+                0,
+                $e
+            );
+        }
+    }
+
+    /**
+     * Build checkout payload from input data
+     *
+     * @param array $data
+     * @return array
+     */
+    private function buildCheckoutPayload(array $data): array
+    {
+        $payload = [
+            'amount' => $this->formatAmount($data['amount']),
+            'currency' => $data['currency'] ?? 'XOF',
+            'error_url' => $data['error_url'],
+            'success_url' => $data['success_url'],
+        ];
+
+        // Optional fields
+        if (isset($data['client_reference'])) {
+            $payload['client_reference'] = substr($data['client_reference'], 0, 255);
+        }
+
+        if (isset($data['restrict_payer_mobile'])) {
+            $payload['restrict_payer_mobile'] = $this->formatPhoneNumber($data['restrict_payer_mobile']);
+        }
+
+        if (isset($data['aggregated_merchant_id'])) {
+            $payload['aggregated_merchant_id'] = $data['aggregated_merchant_id'];
+        }
+
+        return $payload;
+    }
+
+    /**
+     * Format amount according to Wave API requirements
+     *
+     * @param mixed $amount
+     * @return string
+     */
+    private function formatAmount($amount): string
+    {
+        // Convert to string and ensure proper decimal formatting
+        $formatted = (string) $amount;
+
+        // Remove any leading zeros (except for values < 1)
+        if (floatval($formatted) >= 1) {
+            $formatted = ltrim($formatted, '0');
+        }
+
+        // Ensure max 2 decimal places
+        if (strpos($formatted, '.') !== false) {
+            $parts = explode('.', $formatted);
+            if (strlen($parts[1]) > 2) {
+                $formatted = $parts[0] . '.' . substr($parts[1], 0, 2);
+            }
+        }
+
+        return $formatted;
+    }
+
+    /**
+     * Format phone number to E.164 standard
+     *
+     * @param string $phone
+     * @return string
+     */
+    private function formatPhoneNumber(string $phone): string
+    {
+        // If already starts with +, return as is
+        if (strpos($phone, '+') === 0) {
+            return $phone;
+        }
+
+        // Add country code if missing (default to Ivory Coast +225)
+        if (strpos($phone, '225') !== 0) {
+            $phone = '225' . ltrim($phone, '0');
+        }
+
+        return '+' . $phone;
+    }
+
+    /**
+     * Handle client exceptions from Wave API
+     *
+     * @param \GuzzleHttp\Exception\ClientException $e
+     * @throws PaymentRequestException
+     * @return never
+     */
+    private function handleClientException(\GuzzleHttp\Exception\ClientException $e): never
+    {
+        $response = $e->getResponse();
+        $statusCode = $response->getStatusCode();
+        $body = $response->getBody()->getContents();
+
+        $errorData = json_decode($body, true);
+        $errorMessage = $errorData['error_message'] ?? $e->getMessage();
+        $errorCode = $errorData['error_code'] ?? 'unknown';
+
+        $message = match ($statusCode) {
+            400 => "Bad request: {$errorMessage} (Code: {$errorCode})",
+            401 => "Authentication failed: {$errorMessage}",
+            403 => "Access forbidden: {$errorMessage}",
+            404 => "Checkout session not found: {$errorMessage}",
+            409 => "Conflict: {$errorMessage}",
+            default => "Wave API error ({$statusCode}): {$errorMessage}",
+        };
+
+        throw new PaymentRequestException($message, $statusCode, $e);
+    }
+}
diff --git a/src/IvoryCost/Wave/WaveGateway.php b/src/IvoryCost/Wave/WaveGateway.php
index b5ce036..c2ed756 100644
--- a/src/IvoryCost/Wave/WaveGateway.php
+++ b/src/IvoryCost/Wave/WaveGateway.php
@@ -4,10 +4,12 @@
 
 use Bow\Payment\Common\ProcessorGatewayInterface;
 use Bow\Payment\Exceptions\PaymentRequestException;
+use Bow\Payment\Exceptions\ConfigurationException;
 
 /**
  * Wave Gateway
- * Note: This is a placeholder implementation pending official Wave API documentation
+ * Implementation of Wave Checkout API
+ * @link https://docs.wave.com/checkout
  */
 class WaveGateway implements ProcessorGatewayInterface
 {
@@ -16,34 +18,129 @@ class WaveGateway implements ProcessorGatewayInterface
      *
      * @var array
      */
-    private $config;
+    private array $config;
+
+    /**
+     * Wave API client
+     *
+     * @var WaveClient
+     */
+    private WaveClient $client;
 
     /**
      * Create a new Wave gateway
      *
      * @param array $config
+     * @throws ConfigurationException
      */
     public function __construct(array $config)
     {
         $this->config = $config;
+        $this->validateConfig();
+        $this->client = new WaveClient($this->config['api_key']);
     }
 
     /**
-     * Make payment
+     * Make payment - Create a Wave checkout session
      *
      * @param mixed ...$args
-     * @return mixed
+     * @return array
      * @throws PaymentRequestException
+     * 
+     * Expected parameters:
+     * - amount: (required) Amount to collect
+     * - notify_url: (required) Redirect URL on notification
+     * - success_url: (required) Redirect URL on success
+     * - error_url: (required) Redirect URL on error
+     * - currency: (optional) Currency code (default: XOF)
+     * - client_reference: (optional) Your unique reference (max 255 chars)
+     * - restrict_payer_mobile: (optional) Phone number (E.164 format)
+     * - aggregated_merchant_id: (optional) For aggregators only
+     * - idempotency_key: (optional) Unique key to prevent duplicate payments (auto-generated if not provided)
      */
     public function payment(...$args)
     {
-        throw new PaymentRequestException(
-            'Wave payment gateway is not yet implemented. Implementation pending official API documentation.'
+        // Validate required fields
+        $this->validatePaymentData($args);
+
+        // Generate idempotency key if not provided (prevents duplicate payments)
+        $idempotencyKey = $args['idempotency_key'] ?? $this->generateIdempotencyKey();
+
+        // Create checkout session
+        $session = $this->client->createCheckoutSession(
+            [
+                'amount' => $args['amount'],
+                'currency' => $args['currency'] ?? 'XOF',
+                'notify_url' => $args['notify_url'],
+                'success_url' => $args['success_url'],
+                'error_url' => $args['error_url'],
+                'client_reference' => $args['client_reference'] ?? null,
+                'restrict_payer_mobile' => $args['restrict_payer_mobile'] ?? null,
+                'aggregated_merchant_id' => $args['aggregated_merchant_id'] ?? null,
+            ],
+            $idempotencyKey
         );
+
+        return [
+            'success' => true,
+            'session_id' => $session->getId(),
+            'wave_launch_url' => $session->getWaveLaunchUrl(),
+            'amount' => $session->getAmount(),
+            'currency' => $args['currency'] ?? 'XOF',
+            'checkout_status' => $session->getCheckoutStatus(),
+            'payment_status' => $session->getPaymentStatus(),
+            'transaction_id' => $session->getTransactionId(),
+            'client_reference' => $session->getClientReference(),
+            'when_expires' => $session->toArray()['when_expires'],
+            'idempotency_key' => $idempotencyKey,
+            'session' => $session,
+        ];
     }
 
     /**
-     * Make transfer
+     * Verify payment - Retrieve checkout session status
+     *
+     * @param mixed ...$args
+     * @return WavePaymentStatus
+     * @throws PaymentRequestException
+     * 
+     * Expected parameters:
+     * - session_id: (optional) Checkout session ID
+     * - transaction_id: (optional) Transaction ID
+     * - client_reference: (optional) Your unique reference
+     * 
+     * Note: Provide at least one of the above identifiers
+     */
+    public function verify(...$args)
+    {
+        $session = null;
+
+        // Try to retrieve by session ID
+        if (isset($args['session_id'])) {
+            $session = $this->client->retrieveCheckoutSession($args['session_id']);
+        }
+        // Try to retrieve by transaction ID
+        elseif (isset($args['transaction_id'])) {
+            $session = $this->client->retrieveCheckoutByTransactionId($args['transaction_id']);
+        }
+        // Try to search by client reference
+        elseif (isset($args['client_reference'])) {
+            $sessions = $this->client->searchCheckoutSessions($args['client_reference']);
+            if (empty($sessions)) {
+                throw new PaymentRequestException('No checkout session found with the provided client reference');
+            }
+            $session = $sessions[0]; // Get the first matching session
+        } else {
+            throw new PaymentRequestException(
+                'Please provide one of: session_id, transaction_id, or client_reference'
+            );
+        }
+
+        return new WavePaymentStatus($session);
+    }
+
+    /**
+     * Make transfer - Not supported by Wave Checkout API
      *
      * @param mixed ...$args
      * @return mixed
@@ -52,12 +149,12 @@ public function payment(...$args)
     public function transfer(...$args)
     {
         throw new PaymentRequestException(
-            'Wave transfer is not yet implemented.'
+            'Wave transfer is not supported by the Checkout API. Use Wave Business API instead.'
         );
     }
 
     /**
-     * Get balance
+     * Get balance - Not supported by Wave Checkout API
      *
      * @param mixed ...$args
      * @return mixed
@@ -66,21 +163,128 @@ public function transfer(...$args)
     public function balance(...$args)
     {
         throw new PaymentRequestException(
-            'Wave balance inquiry is not yet implemented.'
+            'Wave balance inquiry is not supported by the Checkout API. Use Wave Business API instead.'
         );
     }
 
     /**
-     * Verify payment
+     * Refund a checkout session
      *
-     * @param mixed ...$args
-     * @return mixed
+     * @param string $sessionId
+     * @return bool
      * @throws PaymentRequestException
      */
-    public function verify(...$args)
+    public function refund(string $sessionId): bool
     {
-        throw new PaymentRequestException(
-            'Wave payment verification is not yet implemented.'
-        );
+        return $this->client->refundCheckoutSession($sessionId);
+    }
+
+    /**
+     * Expire a checkout session
+     *
+     * @param string $sessionId
+     * @return bool
+     * @throws PaymentRequestException
+     */
+    public function expire(string $sessionId): bool
+    {
+        return $this->client->expireCheckoutSession($sessionId);
+    }
+
+    /**
+     * Search for checkout sessions by client reference
+     *
+     * @param string $clientReference
+     * @return array
+     * @throws PaymentRequestException
+     */
+    public function search(string $clientReference): array
+    {
+        return $this->client->searchCheckoutSessions($clientReference);
+    }
+
+    /**
+     * Generate a unique idempotency key
+     * Uses UUID v4 format to ensure uniqueness and prevent duplicate payments
+     *
+     * @return string
+     */
+    private function generateIdempotencyKey(): string
+    {
+        // Generate UUID v4 format
+        $data = random_bytes(16);
+        $data[6] = chr(ord($data[6]) & 0x0f | 0x40); // Set version to 0100
+        $data[8] = chr(ord($data[8]) & 0x3f | 0x80); // Set bits 6-7 to 10
+
+        return vsprintf('%s%s-%s-%s-%s-%s%s%s', str_split(bin2hex($data), 4));
+    }
+
+    /**
+     * Validate configuration
+     *
+     * @throws ConfigurationException
+     */
+    private function validateConfig(): void
+    {
+        if (empty($this->config['api_key'])) {
+            throw new ConfigurationException(
+                'Wave API key is required. Please set "api_key" in your Wave configuration.'
+            );
+        }
+
+        // Validate API key format
+        if (!str_starts_with($this->config['api_key'], 'wave_')) {
+            throw new ConfigurationException(
+                'Invalid Wave API key format. API key should start with "wave_".'
+            );
+        }
+    }
+
+    /**
+     * Validate payment data
+     *
+     * @param array $data
+     * @throws PaymentRequestException
+     */
+    private function validatePaymentData(array $data): void
+    {
+        if (!isset($data['amount']) || empty($data['amount'])) {
+            throw new PaymentRequestException('Amount is required for Wave payment');
+        }
+
+        if (!isset($data['success_url']) || empty($data['success_url'])) {
+            throw new PaymentRequestException('Success URL is required for Wave payment');
+        }
+
+        if (!isset($data['error_url']) || empty($data['error_url'])) {
+            throw new PaymentRequestException('Error URL is required for Wave payment');
+        }
+
+        // Validate URLs are HTTPS
+        if (!str_starts_with($data['success_url'], 'https://')) {
+            throw new PaymentRequestException('Success URL must use HTTPS protocol');
+        }
+
+        if (!str_starts_with($data['error_url'], 'https://')) {
+            throw new PaymentRequestException('Error URL must use HTTPS protocol');
+        }
+
+        // Validate amount is positive
+        if (floatval($data['amount']) <= 0) {
+            throw new PaymentRequestException('Amount must be greater than zero');
+        }
+
+        // Validate currency if provided
+        if (isset($data['currency'])) {
+            $currency = strtoupper($data['currency']);
+            if ($currency === 'XOF') {
+                // XOF doesn't allow decimals
+                if (strpos((string) $data['amount'], '.') !== false) {
+                    throw new PaymentRequestException(
+                        'XOF currency does not allow decimal places. Amount must be a whole number.'
+                    );
+                }
+            }
+        }
     }
 }
diff --git a/src/IvoryCost/Wave/WavePaymentStatus.php b/src/IvoryCost/Wave/WavePaymentStatus.php
new file mode 100644
index 0000000..cd417cf
--- /dev/null
+++ b/src/IvoryCost/Wave/WavePaymentStatus.php
@@ -0,0 +1,249 @@
+<?php
+
+namespace Bow\Payment\IvoryCost\Wave;
+
+use Bow\Payment\Common\ProcessorStatusInterface;
+
+/**
+ * Wave Payment Status
+ * Wraps WaveCheckoutSession to provide status information
+ */
+class WavePaymentStatus implements ProcessorStatusInterface
+{
+    /**
+     * Checkout session
+     *
+     * @var WaveCheckoutSession
+     */
+    private WaveCheckoutSession $session;
+
+    /**
+     * WavePaymentStatus constructor
+     *
+     * @param WaveCheckoutSession $session
+     */
+    public function __construct(WaveCheckoutSession $session)
+    {
+        $this->session = $session;
+    }
+
+    /**
+     * Check if payment is successful
+     *
+     * @return bool
+     */
+    public function isSuccess(): bool
+    {
+        return $this->session->isComplete() && $this->session->isPaymentSucceeded();
+    }
+
+    /**
+     * Check if payment is pending
+     *
+     * @return bool
+     */
+    public function isPending(): bool
+    {
+        return $this->session->isOpen() || $this->session->isPaymentProcessing();
+    }
+
+    /**
+     * Check if payment failed
+     *
+     * @return bool
+     */
+    public function isFail(): bool
+    {
+        return $this->session->isPaymentCancelled() || 
+               ($this->session->isExpired() && !$this->session->isPaymentSucceeded());
+    }
+
+    /**
+     * Check if payment failed (alias for isFail)
+     *
+     * @return bool
+     */
+    public function isFailed(): bool
+    {
+        return $this->isFail();
+    }
+
+    /**
+     * Check if transaction is initiated
+     *
+     * @return bool
+     */
+    public function isInitiated(): bool
+    {
+        return $this->session->isOpen();
+    }
+
+    /**
+     * Check if transaction is expired
+     *
+     * @return bool
+     */
+    public function isExpired(): bool
+    {
+        return $this->session->isExpired();
+    }
+
+    /**
+     * Get payment status string
+     *
+     * @return string
+     */
+    public function getStatus(): string
+    {
+        if ($this->isSuccess()) {
+            return 'success';
+        }
+
+        if ($this->isPending()) {
+            return 'pending';
+        }
+
+        if ($this->isFail()) {
+            return 'failed';
+        }
+
+        return 'unknown';
+    }
+
+    /**
+     * Get transaction ID
+     *
+     * @return string|null
+     */
+    public function getTransactionId(): ?string
+    {
+        return $this->session->getTransactionId();
+    }
+
+    /**
+     * Get checkout session ID
+     *
+     * @return string
+     */
+    public function getSessionId(): string
+    {
+        return $this->session->getId();
+    }
+
+    /**
+     * Get amount
+     *
+     * @return string
+     */
+    public function getAmount(): string
+    {
+        return $this->session->getAmount();
+    }
+
+    /**
+     * Get checkout status
+     *
+     * @return string
+     */
+    public function getCheckoutStatus(): string
+    {
+        return $this->session->getCheckoutStatus();
+    }
+
+    /**
+     * Get payment status
+     *
+     * @return string
+     */
+    public function getPaymentStatus(): string
+    {
+        return $this->session->getPaymentStatus();
+    }
+
+    /**
+     * Get client reference
+     *
+     * @return string|null
+     */
+    public function getClientReference(): ?string
+    {
+        return $this->session->getClientReference();
+    }
+
+    /**
+     * Get error details if payment failed
+     *
+     * @return array|null
+     */
+    public function getError(): ?array
+    {
+        return $this->session->getLastPaymentError();
+    }
+
+    /**
+     * Get error message
+     *
+     * @return string|null
+     */
+    public function getErrorMessage(): ?string
+    {
+        $error = $this->session->getLastPaymentError();
+        return $error['message'] ?? null;
+    }
+
+    /**
+     * Get error code
+     *
+     * @return string|null
+     */
+    public function getErrorCode(): ?string
+    {
+        $error = $this->session->getLastPaymentError();
+        return $error['code'] ?? null;
+    }
+
+    /**
+     * Get the underlying checkout session
+     *
+     * @return WaveCheckoutSession
+     */
+    public function getSession(): WaveCheckoutSession
+    {
+        return $this->session;
+    }
+
+    /**
+     * Convert to array
+     *
+     * @return array
+     */
+    public function toArray(): array
+    {
+        return [
+            'status' => $this->getStatus(),
+            'is_success' => $this->isSuccess(),
+            'is_pending' => $this->isPending(),
+            'is_failed' => $this->isFail(),
+            'is_expired' => $this->isExpired(),
+            'is_initiated' => $this->isInitiated(),
+            'session_id' => $this->getSessionId(),
+            'transaction_id' => $this->getTransactionId(),
+            'amount' => $this->getAmount(),
+            'checkout_status' => $this->getCheckoutStatus(),
+            'payment_status' => $this->getPaymentStatus(),
+            'client_reference' => $this->getClientReference(),
+            'error' => $this->getError(),
+            'session' => $this->session->toArray(),
+        ];
+    }
+
+    /**
+     * String representation
+     *
+     * @return string
+     */
+    public function __toString(): string
+    {
+        return json_encode($this->toArray());
+    }
+}