A key area affecting library management is the effective and efficient management and development of information systems. The concept of an information systems development methodology (ISDM) is a management approach that has been virtually ignored in the context of library management. Provides a critique of the literature relating to ISDMs with a view to exploring their use by libraries in the future. Examines the historical development of ISDMs, followed by a definition of the term, and an outline of the requirements for ISDM. Subsequently discusses themes in information systems development in relation to the main types of ISDM associated with them, leading to a consideration of the problems with ISDMs and with their usage. Outlines the need for the further refinement of ISDMs in the light of these problems. Finally, suggests theoretical reasons for the use of ISDMs by library managers.