Information systems development is regarded as a series of distributed activities aiming at allocating resources in order to promote the development and use of computer-based systems. Co-operation means to interrelate those activities and to create a network of human and nonhuman actors to eventually support the use of the system. Applying concepts and terminology of actor-network theory, circulating and (black)boxing commitments of the actors involved are identified as recurrent activities essential to enabling co-operation and to achieving progress in systems development projects, i.e. to encouraging actors to contribute the required resources in due time and place. This framing of ISD is applied to examine co-operation in a case of the implementation of computerised support for the examination administration of a large university. Summing up, the potentials of approaching systems development as networking are evaluated to provide guidelines for co-operation and management in distributed ISD projects.