This document reviews professional learning models for teachers. It discusses the various opportunities for in-service training, including school-based, evening, weekend, and online sessions. Effective professional development is described as innovative, personalized, transformational, and research-driven. It should be collaborative, inquiry-based, and provide continuous support. The document also outlines principles for effective professional learning sessions, including support over time, using varied approaches and active learning methods, being discipline-specific, and including modeling. It concludes that models can be adjusted to be more transformative when they expose teachers to content in small chunks and provide opportunities for implementation and long-term engagement through mentorship and coaching.