This paper deals with the resource-constrained project scheduling problem with flexible work profiles. In this problem, a project contains activities interrelated by finish-start-type precedence constraints with a time lag of zero. In many real-life projects, however, it often occurs that only one renewable bottleneck resource is available and that activities do not have a fixed prespecified duration and associated resource requirement, but a total work content, which essentially indicates how much work has to be performed on them. Based on this work content, all feasible work profiles have to be specified for the activities, each characterized by a fixed duration and a resource requirement profile. The task of the problem is to find the optimum work profile and start time of each activity in order to minimize the project makespan. We propose a procedure to find all feasible work profiles of each activity and we use a genetic algorithm with a new crossover operator to schedule the activities. Computational results on a randomly generated problem set are presented.

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