From leading clinical researchers, this volume presents important recent advances in understanding and treating autism spectrum disorders (ASD) in very young children. The book is grounded in cutting-edge findings on the social-communication behavior of typically and atypically developing infants, toddlers, and preschoolers. The contributors highlight the connections between ASD and specific early social-communication impairments - including problems with joint attention, imitation, and play - with a focus on what clinicians can do to help. Innovative screening and assessment procedures are reviewed, as are evidence-based intervention and prevention strategies. Throughout, attention to both real-world practice and research considerations enhances the book's utility as a clinical reference and text.