Robustness, list of general design principle - http://www.makinggoodsoftware.com/2010/03/02/robustness-the-forgotten-code-quality/ http://www.makinggoodsoftware.com/2011/04/20/10-characteristics-of-a-robust-application-or-service/

How to write readable code - http://www.simple-talk.com/dotnet/.net-framework/writing-maintainable-code/