The rationale for and documented benefits of collaborative planning and teaching are explored in this article. When teachers collaborate on their planning and teaching, they are better able to meet the needs of diverse students and fulfill their legal responsibilities. In addition, the authors describe the multiple ways to collaborate and coteach, including working with students as collaborative partners. Readers are provided with answers to some of the frequently asked questions about collaborative planning and coteaching. The authors describe a method for assessing the effectiveness of teaching teams and provide tips for successful collaborative planning and teaching. The importance of professional development and other forms of administrative support are emphasized. The mutual responsibilities of university personnel preparing future teachers, school administrators, and individual educators are discussed.