Professional development for in-service teachers has always been a crucial aspect of education. The process of continuous learning and skill development is essential for educators to meet the changing needs of students and to improve the quality of education. However, with the rapidly evolving landscape of education and the increasing demands placed on teachers, it has become even more critical to provide relevant, effective, and sustainable professional development opportunities. This book aims to provide educators and policymakers with an in-depth understanding of professional development for in-service teachers. Through a comprehensive analysis of the various strategies, models, and best practices, this book highlights the importance of continuous professional learning and the impact it can have on student outcomes. We have included hypothetical case studies and examples of educators, researchers, and policymakers to illustrate the practical application of professional development strategies. These insights can provide valuable guidance to educators and policymakers in designing and implementing effective professional development programs. This book also examines the National Education Policy (NEP) 2020 and its intentions for the capacity building of in-service teachers. We explore the key provisions of the policy and provide strategies for implementation, highlighting the importance of collaborative learning and leadership development. As editors, we would like to express our gratitude to all the contributors who have shared their knowledge, experiences, and insights to make this book a valuable resource. We also extend our thanks to the publishers for their support and encouragement throughout the writing and publishing process. We hope this book will serve as a useful guide and inspire educators and policymakers to make professional development a priority in their efforts to improve the quality of education for all students.