Microsoft keeps telling us that we should create interfaces for everything and program to them. This is all fine and dandy, but this can become a nightmare when dealing with dynamically loaded libraries. Let us begin with an interface: namespace Interfaces {public interface ICommon {string RequiredField { get; }void DoSomethingWithTheRequiredF... Now, we will create 2 different implementations of the interface. The first will implement ICommon for use with our Sql database: namespace Sql {public ......