This document discusses designing engaging professional development opportunities for teachers. It advocates for professional learning where teachers are active participants, help determine the content, and collaborate with others. Examples of this include TeachMeets, which are informal conferences where teachers lead short sessions on tools and strategies, and EDcamps, which are conferences where session topics are determined the day-of by participants. The document also promotes the use of professional learning networks on Twitter to connect teachers virtually. It provides examples of tools that can be used for flipped learning and job-embedded professional development activities.