Hi, I need to have two objects of the same class present in the working memory at the same time. Both objects can have other nested objects of different classes. The reason is I need to compare data change b/w two objects. E.g; originalObject_A.getPersonTO().getAge() != changedObject_A.getPersonTO().getAge() I am using Drools 3.0, DRLs and DSL. Thanks Saleem Lakhani