Purpose: This paper reports on a study exploring a sustained coaching model of teacher professional development (PD). The study was undertaken with middle school teachers in a small rural school division in Alberta, Canada. The goal of the study was to theorize about the components of the sustained coaching model of PD that supported or was a barrier to teachers engaging in a year-long PD series. Design/methodology/approach: A grounded theory methodology was used to theorize about the components of a teacher PD model that participants viewed as being a support or barrier to their engagement in the PD. Data were collected from two individual participant interviews: one interview at the beginning of the year and one interview at the end of the year. Findings: Findings indicate that teacher PD should include a constant community, accountability to other participants in that community, and a balance of theoretical and practical support and be provided over multiple sessions. In addition, in order for the PD to be sustainable, barriers to engaging in the PD should be minimized. Originality/value: A recognition of the complexity of the factors influencing a teacher's interaction with PD provides a lens with which to consider the potential for a teacher's engagement with PD.