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Patterns & practices Application Architecture Guide 2.0 Beta 2. It’s our Microsoft Playbook for Application Architecture. This is our guide to help solution architects and developers make the most of the Microsoft platform. It's a distillation of many lessons learned. It’s principle-based and pattern-oriented to provide a durable, evolvable backdrop for application architecture. It's a collaborative effort among product team members, field, industry experts, MVPs, and customers. This is the guide that helps you understand our platform, choose among the technologies, and build applications based on lessons learned and proven practices.
Browse / Download the Guide
You can browse or get the guide here: http://www.codeplex.com/AppArchGuide