This chapter discusses the design of a technique for measuring the flexibility of business information systems. It argues that a technique for measuring software flexibility can be designed from existing principles using a qualitative approach. It then describes the design process undertaken to develop a software flexibility assessment technique that could be used to assess the adaptive capacity of business software applications. First, the author introduces the background to the subject and gives the justification for developing a suitable business-oriented measure of software flexibility. He then tackles the design issues and problems that arise when confronted with the complexities of qualitative measurement, before describing the steps of the design process. Afterwards, the stages in the application of the technique are described, with a worked example. Finally the benefits and weaknesses of the technique are discussed, and an opinion expressed as to the usefulness and applicability of the proposed technique.