I wish to create a small series of posts whose goal is to put Scrum and CMMi into perspective. These posts are not intended to advocate one over the other but to share my humble experience on this subject: I just spent more than 3 years within a structure where CMMi was the backbone. As such and having worked as a consultant or project manager, I implemented CMMi practices up to level 4. I approached Scrum 3 years ago but it was not adopted at that time in this structure, and only since the end of 2008 have Scrum projects been rolled out. The question coming up regularly, writing posts on this subject also allows me to organize my thoughts.

Naturally the first thing I’m going to hear (or read) is: CMMi is a model and Scrum a method. So we cannot compare them. I reject this argument in the sense that each company implements CMMi “as it sees fit”, and therefore I’m comparing the implementation of CMMi (as I knew it) to the implementation of Scrum. It is moreover quite amusing to note that this defense of CMMi with respect to Scrum has proliferated recently when the implementation of CMMi is -very- seriously shaken up by the implementation of Scrum.

Yes there is a philosophical opposition between these two methods, which is why one shakes up the other in my opinion. On the other hand it is obvious that the two can in many cases reinforce each other.

I must say that within the organization in which I rolled out CMMi practices, the arrival of Scrum is truly experienced as a breath of fresh air. Especially due to an overly totalitarian monopoly of this doctrine (CMMi). I suppose that in a few years a monopoly of Scrum could just as well be shaken up by a new approach.

The points I hope to address:

• The pair: manager/CMMi leader/Scrum (I draw this terminology (manager/leader) from the excellent: Lean Software Development, an agile toolkit (it reads like a novel, I highly recommend it)).
• For the newcomer, the beginner, what are the benefits and disadvantages of CMMi and Scrum.
• The benefits and risks of CMMi & Scrum, I will try to say when I would rely more on Scrum or more on CMMi, and in which cases the two can coexist or even reinforce each other.
• others perhaps!

I hope not to lose myself, nor to be too ambitious and above all to give you my field arguments (so necessarily they will be “tinted”).