Zend Framework is a simple, straightforward, open-source software framework for PHP 5 designed to eliminate the tedious details of coding and let you focus on the big picture. Its strength is in its highly-modular MVC design, making your code more reusable and easier to maintain. Although it's currently in preview release, take a look—you may be surprised.
Still not sure? Visit [Is Zend Framework right for me?] for more information.