A system for routing communication sessions between a contact and an agent of a contact center is disclosed. The system is arranged to simultaneously connect more than one contact to an agent of the contact center capable of simultaneously handling a plurality of contacts. Typically, the contacts comprise non-voice contacts The system is arranged to obtain a respective time-varying characteristic associated with the various agents indicating an intermediate level of activity for the agents between the agents being unoccupied and the agents being fully occupied with handling contacts. New contacts received at the contact center are routed to an agent based at least partially the time-varying characteristic for the agents.