Pretend play is a central component of child development, but causal inferences about its effects are difficult to make due to inconsistencies in definitions and measurement. A thorough analysis of how pretense is measured, coherences and disagreements in measurement strategies, and the behaviors involved in pretend play is needed. We review 199 empirical articles where pretend play was measured and propose a new hierarchical developmental progression of pretend play, rooted in developmental theory and 50 years of research. We suggest pretend play behaviors are likely to develop additively from least to most psychologically complex in the following order: object substitutions, attribution of pretend properties, social interactions within pretend, role enactment, and pretense-related metacommunication. Researchers must use methods in future studies to better capture this developmental progression. This will strengthen construct validity and improve understanding of the mechanisms within pretend play possibly responsible for positive child outcomes. (author abstract)