Although the organizational capability for agility in IT deployment is crucial to the attainment of enterprise agility, there is scant research on how the capability may be nurtured and leveraged to this end. As improvisation may be an important mechanism for attaining agility in IT deployment, we apply the literature on organizational improvisation to analyze the case of Chang Chun Petrochemicals, one of the largest privately-owned petrochemical firms in Taiwan with a storied history for agile IT deployment. In doing so, a process model is inductively derived that sheds light on how the organizational capability for improvisation in IT deployment can be developed, leveraged for enterprise agility, and routinized for repeated application. With its findings, this study contributes to the knowledge on agile IT deployment and the broader concept of IT-enabled enterprise agility, and provides a useful reference for practitioners who face resource constraints or time pressures in IT deployment.