Flexibility is becoming more important for organisations. Information technology (IT) has been proposed as a tool which can aid the attainment of flexibility. However, IT may also reduce an organisation's flexibility. In order to assess the extent to which IT enables or inhibits flexibility, a definition capable of operationalisation is required. This paper reviews existing literature and finds it wanting. Hence, the paper provides an inclusive definition which allows the measurement of flexibility. Flexibility is defined as 'the capacity to adapt' across four dimensions; temporal, range, intention and focus. These dimensions define areas within which flexibility can be achieved. The extent of flexibility can be measured by its metrics; efficiency, responsiveness, versatility and robustness. These four metrics measure the temporal and range dimensions. The intention and focus dimensions are operationalised within the context of the specific IT to be evaluated. The implications of this are discussed. (C) 2000 Elsevier Science Ltd. All rights reserved.