This book explores the intersection of motor behavior, disability, and inclusive practice across the lifespan. The book integrates foundational theories of motor development with applied approaches to assessment, instruction, and intervention for individuals with disabilities. The book provides both conceptual frameworks and actionable strategies grounded in empirical research. Drawing upon interdisciplinary expertise from leaders in the fields of motor development, therapy, and adapted physical education, this text offers a comprehensive examination of motor behavior as it relates to disability, function, and participation. The book's structure progresses logically from theory and assessment to applied practice and lifelong activity engagement, promoting a holistic understanding of movement across the lifespan.