Purpose: The purpose of this two-part paper is to develop a process model of unlearning established organizational routines. The model traces the interactions among three unlearning sub-processes: ostensive aspects of initial destabilization of an established routine; performative aspects of ongoing discarding-from-use of old behaviors and experimenting with new ones; and ostensive aspects of eventual release of prior understandings and development of new ones. Design/methodology/approach: The paper draws on evidence from psychology and cognitive science to explain the mechanisms underlying organizational processes of unlearning embedded routines. Findings: The proposed model contributes to enriching current understanding of unlearning organizational routines without contradicting it. Consistent with prior understanding, destabilizing an old routine may lead to discarding it, and further discarding-from-use is likely required for continued destabilization of embedded routines. Again, consistent with prior understanding, experimenting with new behaviors may be a desired outcome of unlearning an old routine, and ongoing experimentation is likely required to sustain unlearning embedded routines. Originality/value: The organizational unlearning literature provides many examples of organizational members relinquishing old routines to then make new learning possible and also provides little insight into the processes by which this occurs. The paper addresses this gap by modeling the mutually reinforcing nature of three unlearning sub-processes.