Peer coaching involves teachers observing each other's classrooms to provide constructive feedback to improve teaching skills. It works best with a structured process where roles and expectations are clear. Collegial development groups are another form of professional development where teachers lead their own discussions about student work and teaching practices. There are two types: study groups which explore new ideas, and critical friends groups which focus on examining student work and teacher thinking. For collegial development groups to be an effective teacher supervision process, administrators must facilitate with equal participation and use annual reports to analyze impact.