Looking at my bookshelf, there are three books that I've re-opened as references for a while that have a significant impact on my current work: 1. Refactoring/

Looking at my bookshelf, there are three books that I've re-opened as references for a while that have a significant impact on my current work: 1. Refactoring/Fowler 2. Design Patterns/Gang of Four 3. The Art of Unit Testing/Osherove Although, the last book (Unit Testing) is C# specific, what I appreciated was the open discussion of using techniques and tools, rather than ideology.