We are developing and validating a novel and innovative data collection space called the SmartPlayroom, designed to pair naturalistic exploration and action with the precision of computerized automated data collection and analysis. Behaviors include movement kinematics, language, eye movements, and social interaction while a child performs naturalistic tasks, plays and explores without instruction, walks or crawls, and interacts with a caregiver. The space is equipped with mobile eye tracking, wireless physiological heart rate and galvanic skin response sensors, audio and video recording, and depth sensor technologies. The goal of our project it to demonstrate the scientific advantage of naturalistic measurement, and in the process, to provide data to further develop flexible computer vision algorithms for automated behavioral analysis for use with 4-9 year-old children in the SmartPlayroom. The SmartPlayroom will be a valuable tool to aid understanding of child development and for improving diagnosis of developmental disorders such as autism spectrum disorder.