The psychometric properties of the Infant-Toddler Environment Rating Scale-Revised Edition (ITERS-R) were examined using 153 classrooms from child-care centers where resources were tied to center performance. An exploratory factor analysis revealed that the scale measures one global aspect of quality. To decrease redundancy, subsets of items were selected randomly and by experts who rated items according to ease of administration and importance to quality. The shorter subsets demonstrated good discriminant validity, adequate to good psychometric properties, and high associations to the full ITERS-R score. They also demonstrated similar associations to staff education and staff-to-child ratio, as the full instrument. The best assessment of quality was demonstrated by the shortened subset that included items that assess both structural and process features of quality. Multilevel-analyses indicated that classrooms from the same providers score more similarly on ITERS-R than classrooms from other providers. The implications for using the ITERS-R in high-stakes contexts are discussed. (Contains 5 tables.)