This is a discussion oriented course focusing on the general concepts of stem cell biology in various tissues from both vertebrates and invertebrates. Discussions will be led by the instructors and each student will be expected to participate actively in the discussion of the topics. Assigned readings for each topic are expected to be read before each meeting and will form the basis of the discussion. However, the topics will not be entirely confined to the material presented and students may wish to read more widely, using the assigned references as a starting point. Discussion will focus on models and concepts rather than technical details.