Yesterday, someone described us at CQ2 as "Software Efficiency Experts" . Probably, because we try to eliminate waste in software development, and we continually search for, and find practices that work well for us and our clients.
But what about Effectiveness? It is nice to reduce costs, but if you develop the wrong things, you are getting nowhere. You are getting there more cheaply than otherwise, maybe faster as well, it is all well tested, but it still is the wrong software!
The best way, in my opinion, to increase effectiveness is to eliminate waste in requirements:
Now that we are developing the right thing, we can focus on developing the thing right. What works well for us in this respect, is Test Driven Development (which makes reliable software cheaper to build and maintain than unreliable software), Refactoring and some other techniques from Extreme Programming in combination with increasing the personal effectiveness of development team members and better and more enjoyable teamwork through e.g. Retrospectives.
Cost-effective is a nice word to describe this, because it focuses on cost (efficiency) as well as on value (effectiveness).