The production planning and control process is performed within complex and dynamic organizations made up of customer expectations, equipment, materials, people, information, and technologies. Changes in both internal and external factors can create a variety of unforeseen events, which make initial plans unfeasible or obsolete during production execution. How to effectively handle the unscheduled events and take corrective actions still remains a central question to academics and practitioners. In this paper, we explore this issue through a review of the relevant literature and an in-depth field study. The paper proposes a framework for characterizing and classifying the events and event handling process.