Often the demand for vehicle sharing services varies significantly in space and time. Some stations/regions may run out of units due to uneven demand, while concurrent end journeys may overload others. To meet user trip demand and enhance user satisfaction and usage, a relocation procedure is a solution to rebalance vehicles in various stations. This thesis focuses on free-floating car sharing systems employing an operator-based relocation process to mitigate the imbalanced vehicle distribution problem. Many previous works have already confronted the repositioning problem, optimising the relocation process only based on knowledge about the immediate future. The methods developed in this thesis aim at maximising the satisfied mobility demand avoiding a greedy and possibly short-sighted approach and taking into account demand forecasts over a longer time period and over multiple relocation steps.