They talk about how you can use these ideas to better understand your clients' needs and to build software that closely models their business. They also talk about where these ideas don't work so well, and some of the challenges and trade-offs you face when trying to build software this way.

• Shawn's blog
• The RSpec Book
• everzet's Introduction to BDD
• everzet on Modelling by Example
• Domain Driven Design Quickly
• "Domain Driven Design" by Eric Evans
• "Implementing Domain Driven Design" by Vaughn Vernon
• Ross Tuck's blog