When you build a business application, you have a different set of concerns that go beyond quickly throwing together an application and getting it to the marketplace. You need to think more about how to build the application in a way that is maintainable, testable, and easy to evolve over time to suit the business needs. Microsoft patterns and practices has put together guidance on how to do this, called Project Kona. In this session, learn directly from one of the p&p team members how to leverage that guidance for building your own business applications. Learn how to implement the MVVM pattern using some base class support that lets you handle navigation in your view models, deal with validation and present it even though the platform doesn't have built-in support for it, call services and integrate service validation results, handle authentication and persistence in your application, and more.