This paper questions the physical environmental adequacy of the Infant/Toddler Environment Rating Scale (ITERS) developed by Thelma Harms, Debby Cryer, and Richard Clifford at the University of North Carolina, Chapel Hill. ITERS is a 35-item scale designed to assess the quality of center-based infant and toddler care, and one of a family of child care rating scales developed by its authors. It is based on a broad definition of environment, considering not only the organization of space, but interaction, activities, schedule, and provisions as well. An evaluation of the 396 detailed descriptors that are used to score a center on the scale items found that only 35 were directly related to the physical environment of the center. Some test items are confounded with behavioral use patterns. The scale is also silent on important issues, such as the use of traditional, self-contained classrooms versus modified open spaces; the pros and cons of different organizational patterns; the environmental characteristics of a center that facilitate developmentally appropriate play activities; and the environmental impact of age-mixing. Items measuring peer interaction and caregiver-child interaction lack any descriptor that relates to the physical setting. Other strengths and weaknesses of the ITERS are discussed. (MDM)