In 1990 Alan Meyer, Geoffrey Brooks, and James Goes published a 2x2 framework for categorizing theories of change used by scholars in management and organization studies. This framework distinguished modes of change (continuous vs. discontinuous change), and levels of analysis (organization-level vs. field-level change). This chapter (1) summarizes, evaluates, and extends the framework in light of subsequent work, (2) identifies new social mechanisms that have been posited as causal mechanisms driving discontinuous change within organizations and organizational fields, and (3) proposes fruitful constructs, methodologies, and directions for future research on change in and around organizations.