# Implementing request-response systems in Amazon SQS
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When implementing a request-response or remote procedure call (RPC) system, keep the following best practices in mind:
+ **Create reply queues on start-up** – Instead of creating reply queues per message, create them on start-up, per producer. Use a correlation ID message attribute to map replies to requests efficiently.
+ **Avoid sharing reply queues among producers** – Ensure that each producer has its own reply queue. Sharing reply queues can result in a producer receiving response messages intended for another producer.

For more information about implementing the request-response pattern using the Temporary Queue Client, see [Request-response messaging pattern (virtual queues)](sqs-temporary-queues.md#request-reply-messaging-pattern).