As scripts become more and more complex, the difficulty of maintaining them increases dramaticallyespecially if you are programming in a procedural style. The concept of object-oriented programming (OOP) is to provide a real organizational structure to your scripts through encapsulation. Although PHP 4 introduced the notion of OOP into PHP, it could not be considered a true OO implementation. Because of the significant limitations in PHP 4 in this respect, the object model in PHP 5 has been completely redesigned to more accurately reflect the academic definition of OOP. This chapter will guide you through the use of objects in PHP 5 and point out along the way how what you may be accustomed to in PHP 4 has changed.