Despite the widespread use of classroom videos in teacher professional development, little is known about the specific effects of various types of videos on teachers´cognitive, emotional, and motivational processes. This project investigated the processes experienced by 10 eighth-grade mathematics teachers while they analyzed videos of their own or other teachers´classroom instruction. Findings indicate that teachers viewing videos of other teachers are more deeply engaged in analysis of problematic events. Counterintuitively, observing videos of others corresponds to higher emotional-motivational involvement. Results support the conclusion that observing one´s own videos requires more prearrangement and scaffolding than observing others´videos.