Abstract The external environment of a corporation is one of the major determinants of its strategy. While this view is readily accepted, the tools to monitor this important determinant are still relatively underdeveloped. The authors have developed a managerial process which fills this gap by enabling an organization to assess its external environment effectively and economically. The approach helps executives identify major forces for strategic change in the market and non-market dimensions of the environment. The relevance of these changes is determined by measuring their impact on the mission and the strategies of the company. The process, furthermore, provides a starting point for assessing an organization's capabilities to respond to these forces for change.