A MULTIPROJECT PERSPECTIVE OF SINGLE-PROJECT DYNAMICS

Heretofore, the study of software project management has been limited to a single-project-in-isolation perspective, largely overlooking the interdependencies among projects. This is despite the fact that few, if any, actual software projects are carried out in complete isolation. In this work, I relax the project-in isolation assumption and attempt to demonstrate that interactions and interdependencies among projects can have a significant influence on project behavior. As such, the behavior of an individual project in isolation may be very different from its behavior when it interacts with other projects. The research vehicle for this study is a multiproject system dynamics model that was developed on the basis of field studies in five organizations. The results of a case study conducted in a sixth organization to test the model's accuracy in replicating the behavior of two concurrent software projects are presented. In the final section of the paper, I conduct a number of model-based controlled experiments to assess the effects of inter-project interdependencies on project behavior. The results suggest that scheduling and work force allocation decisions in one project can significantly influence the cost and duration of the other. The significance of these results is twofold. First, they highlight a fundamental deficiency in the formulation of the current generation of estimation tools. Second, they underscore the perils of parochial decision making in a multiproject environment.