Sound technical knowledgeA sound foundation in .NET framework and any technology on top of it is a prerequisite of a good .NET developer. He must have good command on C# or VB.NET. For web technologies he should have knowledge on The Official Microsoft ASP.NET Site, JavaScript or Angular JS or other scripting languages, MVC and for windows desktop applications he should have knowledge on WPF and MVVM techniques.ExperienceExperience is a very important quality of a good .NET developer. 3-4 years of experience can be considered as a standard experience.Ability to immediate response.NET developer should be able to quickly respond the changes and modifications of the application. It will save both time and money.Ability to refactor codeSometimes a developer needs to start working on existing application where the code quality may not be good. To improve the code quality, he should be able to restructure the code without changing the external behavior.Ability to use existing codeA good developer is expert in finding codes which are already available in different sources and use them. Thus h can save time.Ability to testA good .Net developer can test the essential part of the code. He knows well what to test. He tests only the essential part and does not waste time testing unnecessary codes.