Last week something caught my eyes. How scattered business logic can become if you let your binary expressions be used “here and there” when matching entities against certain rules. Logic for a single entity, e.g Customer can be used all over your codebase. This article will show you a way to get around this and to get a central repository of rules/predicates that can be applied to entities and makes your daily unit test writing easier. I will use simple operator overloading for accomplishing this.