REST Frameworks for PHP

Zend Framework has client and server classes for REST. WSO2 WSF/PHP too has comprehensive support for REST, both client and services.

If your requirements are simple and you are just starting to use REST services, Zend Framework would be a good choice to start with. But if you are going form design to implementation and your application is of enterprise grade, then you have to consider WSO2 WSF/PHP. WSF/PHP is designed in such a manner that you can map your resource design, along with HTTP verb mapping and custom URI mapping to business operations with minimal effort.