Domain Driven Design
patternAdopt
While I no longer use DDD as part of my current job, I have adopted it for personal use and I am pushing for its use on my current team.
Use
While the original Domain Driven Design book is an intimidating read, I believe it is essential to know at least a little bit of DDD when writing large systems.
Learning DDD was like bringing order to a complex system where there was chaos before, everything has its own place and responsibility, and it is easy to understand.