While many architects use PHP for projects, they are often not aware of the power of PHP in creating enterprise-level applications. This book covers the latest version of PHP - version 5 -- and focuses on its capabilities within a multi-tier application framework. It contains numerous coding samples and commentaries on them. A chapter discusses object orientation in PHP as it applies to the multi-tier architecture and other chapters discuss HTTP and SOAP, the two communication protocols most useful in tying together multiple layers. There is also coverage of database design and query construction as well as information about tricks you can use in generating user interfaces.