Abstract: A transfer port system to allow material to transfer between two dockable sterile environments. Two doors provide access to the sterile environments. A peripheral flange frames one of the doors while another peripheral flange forms the opening to the other sterile environment. Doors connect to one another, when the sterile environments are docked, and then move as a unit into the one sterile environment in order to allow the material transfer. Outer and inner gaskets seal the sterile environments and with the peripheral flanges form an interface between the sterile environments during material transfer. The portions of the gaskets and peripheral flanges that were exposed to the unsterile ambient prior to docking are actively heated in order to maintain sterility during the time when the sterile environments are docked and prior to the time that the doors are moved to the open position. The doors can be connected to one another prior to their opening by vacuum.