_title; } public function setTitle($title) { $this->_title = $title; } } class FooBookPrototype extends BookPrototype { protected $_category = 'Foo'; public function __clone() { } } class BarBookPrototype extends BookPrototype { protected $_category = 'Bar'; public function __clone() { } } $fooPrototype = new FooBookPrototype(); $barPrototype = new BarBookPrototype(); // now lets say we need 10,000 books of foo and 5,000 of bar ... for ($i = 0; $i < 10000; $i++) { $book = clone $fooPrototype; $book->setTitle('Foo Book No ' . $i); }