SAMS Subject Classification: 23

A prominent public transport company which provides a passenger transport service in the form of daily timetabled bus trips in and around the city of Cape Town currently performs the assignment of vehicles and crew members to these trips manually. This assignment process is characterised by the solution of three different combinatorial optimisation problems, namely the vehicle scheduling problem (VSP), which entails the assignment of vehicles to trips over a scheduling period, the crew scheduling problem (CSP), which entails the assignment of crew members to trips over a scheduling period, and the crew rostering problem (CRP), which entails the assignment of crew members to trips over a rostering period (whereas a scheduling period typically spans one day, a rostering period typically spans several days). The aforementioned sub-problems are traditionally solved sequentially due to their considerable individual computational complexities. The public transport company in question has, however, launched a research project in which the objective is to develop a method for solving all of these sub-problems simultaneously (known in literature as the integrated vehicle crew rostering problem) while attempting to minimise a cost function. Results obtained when adopting the aforementioned solution method are presented and costs are compared with the status quo in the context of real timetabled trips data obtained from the transport company.