The study investigated a coach's use of a theoretical framework called the Model of Mastery to assist three teachers in becoming self-regulated in the teaching of writing workshop by moving them through three settings: acquisition, consolidation, and consultation. The goal of the coach was to assist teachers in developing expertise in procedural, declarative, and strategic knowledge as it relates to writing in order to mentor others. The findings indicated the Model of Mastery allows a coach to stay focused on where the teachers are in their learning and to determine change over time in the development of their professional knowledge. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]