This chapter focuses on the key components of screening and comprehensive ASD assessments, which include the diagnostic interview, cognitive/developmental measure, adaptive measure, direct play-based observation, record review, and medical evaluation. Common cognitive, receptive, and expressive language, and adaptive profiles are outlined. The relative strengths and weaknesses of specific measures for preschoolers and school-age children are discussed as well as profiles that are commonly seen in children with ASD. Direct play-based measures such as the ADOS-2 and CARS-2 are compared with various autism rating scales. The role of the speech and language therapist in the assessment of pragmatic language is also included, and case examples and sample interview questions are provided.