This company was fully committed to walk the talk, they decided to do what needed doing.
After the developers gave their thumbs up, it took about a month to set everything in motion. This is is a mid size company with over 300 employees at their head quarters. Once we got the ball rolling the company was ready. They had torn down walls to create right sized team rooms, organized great Story Boards or shall I say walls. Again, they were serious. In the first two weeks, apart from coaching the teams, I trained ten people as Scrum Master (PSM) and ten more as Product Owner (PSPO). We didn't really know who is going to fulfill which role, we just knew that the future person would be coming from those groups. Also, the intention was to really create an agile culture and what could be better then to reach out and train and convince as many people as possible. After that I gave about ten introductions to Scrum, each lasting about two hours; the target audience was marketing, sales, support and other departments on the projects periphery.
For the frist two sprints -- 2 weeks in duration -- I was coaching a 100%. Essentially being a Scrum Master. After two Sprints I was only around at the beginning and at the end of the Sprint. During my absence the teams had the chance to walk on their own without training wheels, getting first-hand experience into when they started to struggle. After 5 Sprints the teams decided on their own who should replace me as the Scrum Master. In the remaing four Sprints, I worked closely together with my replacements. My presence became less and less. At the end it was about 20% of the time. By the end of last year, they didn't need me anymore and I moved on.
This whole engagment lasted about four month in calendar time and about two month of coaching from my side.
Now, during the open hours, I had the chance to meetup with a couple of guys from the old teams and we chatted a little. It was a great to see, that all of them really had drunken the agile CoolAid. They did not roll back one inch - instead they kept on pushing hard. Now, there are three teams and more coming soon.
For me and my company effective agile. this coaching approach has become my favorite modus operandi for change engagements.
By the way, the last two releases were two and six weeks early! It humbles me to know, that I was the initation.