Practice theories of implementing change are lagging behind process theories of organizational change and development. To address this gap, this paper examines common breakdowns in implementing four process models of organization change: teleology (planned change), life cycle (regulated change), dialectics (conflictive change), and evolution (competitive change). Change agents typically respond to these breakdowns by taking actions to correct people and organizational processes so they conform to their model of change. Although this strategy commands most of the attention in the literature, we argue that in many situations managers and scholars might do better if they reflected on and revised their mental model to fit the change journey that is unfolding in their organization. Copyright by the Academy of Management; all rights reserved.