The SEQ (Version 1) is a brief (10–15 min) caregiver report instrument designed to evaluate sensory processing problems in young children (ages 5–72 mo) with autism and related DD. The SEQ is designed to be used as a supplement to diagnostic developmental assessments. The SEQ measures hyper- and hyporesponsive patterns across social and nonsocial contexts; it yields four-dimensional subscale scores as well as a total score. The items reflect five sensory domains ( Tactile, Auditory, Visual, Vestibular–Proprioceptive, and Gustatory–Olfactory). Caregiver responses are based on a 5-point Likert scale, ranging from 1 (almost never) to 5 (almost always.) Higher scores are indicative of more sensory processing problems. In addition to the quantitative responses of child behaviors, the questionnaire includes qualitative questions regarding parent compensatory strategies used in response to the sensory processing problems experienced by the child.