A contemporary view of early childhood motor development considers environmental influences as critical factors in optimal growth and behavior, with the home being the primary agent. However, there has been minimal research examining the relationship between motor development and the home. The present study addresses this gap with the goal of creating an innovative parental self-report instrument to assess the quality and quantity of factors (affordances and events) in the home that are conducive to enhancing motor development in children ages 18-42 months. Following initial face validity determination, expert opinion feedback and selective pilot testing, construct validity was examined using 321 Portuguese families. Factor analysis techniques were used to: (a) compare competing factorial models according to previous theoretical assumptions, and (b) analyze the fit of the preferred model. Of the five plausible models tested, the five-factor solution provided the best fit to the data. Reliability was established through the scale reliability coefficient with a value of .85. The findings of this study suggest that the affordances in the Home Environment for Motor Development Self-Report is a valid and reliable instrument to assess how well home environments afford movement and potentially promote motor development.