We develop a model to enable engineering professional services firms to improve the management of their competitive resources, i.e., skilled engineers, to be better able to respond to customer demand. The model was informed by semistructured interviews with senior executives from engineering, information technology (IT) services and technical consulting firms. As a result, we capture many of the complexities associated with the resource planning process in the professional engineering services sector. In the resulting model, the key attributes of supply, demand, and operations constraints are identified. Based on information obtained from the interviews, a number of test firms are created. We then use these test firms to study the impact of various resource planning policies on firm performance. These policies include the skill mix and profile of skilled employees, limits on the number of concurrent projects to which an employee can be assigned, and policies governing employee cross-training and hiring. The impact of these policies is evaluated in terms of business metrics, such as the project completion rate and net revenue. Finally, our model is extended to capture a multiphase rolling planning horizon, where projects may span multiple phases with the goal of ensuring consistency in employee assignment to projects. [ABSTRACT FROM PUBLISHER]