Agile is the new buzzword. And it's achieved more than critical mass. Many Drupal shops operate on an agency model - and most agencies know that an increasing number of contracts and projects are nowadays only being awarded if you are "agile". However, once inside a fixed-price agile contract, how do I deliver? Especially, if everything sounds more like a trap where the client isn't just allowed to change his mind but in theory is also encouraged or at the very least welcome to do so?

Let's discuss some specific solutions to specific problems in a way that everything makes sense to you.