This paper describes the development and use of a relatively new, widely adopted, teacher-rated authentic assessment measure and presents an overview of findings from four studies regarding its reliability and validity. The Teaching Strategies GOLD(R) is an assessment system designed to assess the development and learning of children birth - kindergarten, inclusive of children with disabilities and English language learners. Study samples were large and diverse. Children attended Head Start, private child care, and school-based programs in all areas of the United States and were representative of the nation's population of similarly aged children. Overall results indicate that the GOLD(R) yields valid and reliable inferences for the intended population and that teachers are able to use the measure to accurately assess children's development and learning across the designated age range. Limitations and implications for practice and future research are discussed. (author abstract)