How-to implement Specification Pattern with Entity Framework ?
For those who want a primer, visit this link.
Understand Specification for Entity Framework:
Read this. This covers the following very important points. In any sort of real world application you will quickly want to chain multiple specifications together. This is referred to as composing specifications. You will need to gain a grasp of some of the caveats for the resolution of specification composition within Linq to Entities. You need to know this because using Linq to Entities is the desirable approach to expressing specification satisfaction criteria.
You should have enough information to implement the pattern. Keep googling. Doing this for EF is not entirely simple but well worth the effort. This is a very interesting implementation.