We probably all know that gathering requirements is not as easy as it may sound. And it’s also pretty clear that the issue is not primarily around technical things but communication and people. I can recommended this book (link to amazon.com and amazon.de) to everyone who is interested in or works in that area.
I came across the book during a project where requirements gathering was a very important aspect. I had certainly done this before on numerous occasions. However, this book greatly increased my insight into the underlying mechanisms, patterns etc.