This fully revised third edition explores the childhood and adolescent experiences of transgender persons, providing foundational knowledge for social workers and related professions about working with trans and gender expansive youth. Organized through the lens of four distinct forms of knowledge – knowledge of lived expertise, community-based knowledge, practice knowledge, and knowledge obtained through formal/traditional education – this text balances discussion of theory with a range of rich personal narratives and case studies. Updates and additions reflect recent changes to the WPATH guidelines and the NASW Code of Ethics, include brand new material examining the origins of gender identity and non-binary identities, explore intersectional identities, and offer expanded content considering trauma-informed interventions and ethical issues. Each featuring at least one trans or gender expansive author, chapters present concrete and practical recommendations to encourage competent and positive practice. With a focus on both macro and micro social work practice, this book will be a valuable resource to any social service practitioners working with children or adolescents.