Electric vehicle-sharing systems have been introduced to the cities to increase mobility, and reduce congestion and pollution. These systems give their users self-service access to vehicles scattered around cities and rent them for short time intervals throughout the day. Carsharing systems contribute to the integration of public transport by filling the gap between the flexibility offered by privately-owned car transportation and fixed-route and -schedule mass public transport services. They have the potential to decrease the car ownership, vehicle kilometres travelled, parking space need, and footprint of personal transport. They are grouped according to the flexibility they offered to their users. In (station-based) one-way systems, users are allowed to return the cars to the available parking spots of any station of the system whereas round-trip systems restrict users to return vehicles to their pick-up stations. In this talk, I am going to cover three different one-way (electric) vehicle-sharing problems that we worked on for different levels of decisions. The first paper covers a strategic-tactical level decision that was used to introduce the flexibility of one-way trips to a round-trip system. The second paper handles an operational planning problem that aims to look for the relationship between the customers' acceptance level of spatial and temporal flexibility, and the profitability of the system. The third paper deals with a real-time operational application of a vehicle-sharing system and proactive relocation policies based on Markov chain dynamics. I will conclude my talk with a summary of the important contributions so far and some open questions from the research field.