The other day I came across the Clean Code Developer Initiative, initiated by two German software consultants, and inspired by the book "Clean Code".
They say that to be a true professional in software development, just earning money with it, is not enough. They suggest a common set of principles, values and best practices that should be followed by all true professionals.
With most of their principles I fully agree, for example:
Keep It Simple, Stupid (KISS) and You Ain't Gonna Need It (YAGNI) - also see my Mission page why I think these are some of the most important principles in Software Development - they are far too often violated
Favor Composition Over Inheritance - Beginners tend to use Inheritance in Object-Oriented Systems far too often; in most cases, Composition is much better, because of loose coupling, better testability and flexibility
Root Cause Analysis - Analyze thoroughly before acting
Reflect daily - Always ask yourself, is it really the right way I,m doing it?
Continuous Integration including Automated Integration Testing
SOLID principles, from Single Responsibility to Dependency Inversion
... and so on
For more details, see the www.clean-code-developer.de web site - currently only in German though. Highly recommended reading for all professionals in Software Development!