Simple way to seperate the business logic
I finished my core application and now I must start adding different business rules for different clients. What is a simple way to achieve this?

I am using C++ in visual studio 2008 and I used MFC for the interface. 
Simple way to seperate the business logic
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I finished my core application and now I must start adding different business rules for different clients. What is a simple way to achieve this?

I am using C++ in visual studio 2008 and I used MFC for the interface. 