Abstract: A computer implemented method for solving a scheduling or capacity planning problem of a workforce of a service center, given an anticipated workload, is disclosed. The method includes the steps of calculating the number of workers and skills required in order to supply the adequate level of service; determining the number of workers required at a given period of time; and assigning specific workers subject to specific constraints to a specific period of time, by constructing and solving a mixed integer programming problem. The steps are implemented in either of computer hardware configured to perform said steps and computer software embodied in a non-transitory, tangible, computer-readable storage medium. Also disclosed are corresponding computer program product and data processing system.