This paper seeks to enrich the literature of operations and supply chain management through the development of the concept of Reactivity and the introduction of related performance indicators. Reactivity explains the capability to perform operationally and economically under unexpected conditions. A qualitative investigation has aimed to identify useful managerial practices to be adopted to properly perform Reactivity, while an empirical analysis has tested the relevance of each practice as well as the economic benefits that Reactivity provides. The findings suggest that managers and practitioners should develop a Reactivity orientation because it benefits firms' economic performance when an unexpected event occurs; in addition, several recommended managerial practices should be undertaken to ensure its correct implementation. © 2013 Elsevier B.V. All rights reserved.