This session presents a research-based audit of one of integral theory’s central claims: that diverse developmental models can be synced along a single altitude axis because they are tracking shared deep structures of meaning-making. The Institute of Applied Metatheory’s work aims to contribute to an integrative metatheory 2.0—one that retains the explanatory ambition of earlier systems builders while meeting contemporary standards of operationalization, measurement, and empirical accountability. This presentation will offer attendees a clear, non-reductionistic way to bring evidence to bear on altitude claims. The core methodological move is to treat hierarchical complexity—measured with the Lectical Assessment System—as a content-neutral, domain-general proxy for “altitude.” Specifically, data will be shared about the following lines: Cognition (Piaget), Faith (Fowler), Orders of Consciousness (Kegan), Ego (Loevinger/Cook-Greuter), Values (Graves/SD), and Worldview (Gebser).