Quality Rating and Improvement Systems (QRIS) for early childhood programs and school-age care are being implemented in more than half of the states as a strategy to improve program quality for young children. QRIS provide parents with information to help them select high quality education and care for their children. QRIS give early childhood programs and school-age care providers incentives and resources to improve quality, working through several manageable steps or levels, plus public recognition for their achieved quality levels. An important long-term goal of QRIS is to improve child development and school readiness outcomes for children. This Brief examines key issues in measuring children’s development when evaluating QRIS.