This book provides a timely and much-needed critical legal review of children's participation in healthcare that goes beyond merely documenting the extent and scope of participation, and explores the importance, definition of, and barriers to their meaningful participation. Addressing a gap in the literature, the book uses a combination of empirical data, childhood and participatory theory, and legal analysis to study the participation of children and young people in the medical context from a child's rights perspective. Centring the unheard and underrepresented lived experiences of recent and past child patients, and doctors, the book uses Interpretative Phenomenological Analysis, a methodology traditionally used in psychology, to provide a refreshing and unique exploration of children's participation in their healthcare. The book explores to what extent national law and international non-binding conventions have created a 'right' to participation, studies the application of national law in clinical practice asking whether the law facilitates meaningful participation, and analyses the interaction between law and quasi-legal regulations. The book will be useful for academics, children's activists, and legal and clinical practitioners.