Hey, these are 2 different positions and you need Architect only for huge system in enterprise domain.Usually you have Solution Architect, Domain Architect and Enterprise Architect, according to the complexity of the solution and the enviroment. In small team or organitation sometime the Solution Architect is also a developer but you are in limit situation where may be you don't need a architect becuase you application is not too huge. Cheers, Antonio

Hi Omar, Loose Coupling it isn't a pattern, but a programming best practice. You are talking about Inversion of Control and Dependency Injection topics. I suggest you to read the following article to introduce yourself in the question : http://www.codeproject.com/Articles/25733/Dependency-Injection-Pattern-Loose-Coupling