Abstract This paper describes a seven-step approach to producing a Business Environment Scanning System for Corporate Planning. The authors stress the need to monitor different environmental areas through a set of Environmental Descriptors indicating the developments, trends and events in the environment. These Descriptors are visible in the form of weak signals. The authors link the impact of these Descriptors on the long-range planning system of a company through a set of Environmental Indicators and their Influence Diagrams. The process of monitoring is carried out by a group of managers who act as Environmental Radars. The role of Radars is to monitor the Descriptors, intercept and amplify the weak signals using an Environmental Data Base and generate the Environmental Scenarios. The system works on a continuous basis and assists top management in defining the size and direction of strategies and programmes for achieving long-range objectives.