This theme issue of "Educational Leadership" arose after asking a group of educators about their current challenges and they mentioned the intricacies of co-teaching. The topic was broadened to look at not only co-teaching with specialists--particularly, special needs educators and ELL educators--but all team teaching across content areas, student teaching, and coaching. The purpose was the explore two questions: What does the research on teaching together say? and What are the best ways to practice it? The authors in this issue describe the protocols and practices that improve the changes for co-teaching to benefit both students and educators.