The Russian-built Universal Docking Module (UDM) is a hub for an additional four modules of the Russian built portion of the International Space Station. It will be docked to the Nadir (earth facing) Zvezda service module docking port. The other end of the UDM will have four docking ports to accomidate the Russian Science Modules and SO2 Docking Compartment. The UDM will also have an additional Environmental Control Systems to allow for additional ISS crew members. It will provide docking ports for Russian and American space vehicles. Plans call for Research Modules 1 and 2 to be sent into orbit in separate launches. The launch vehicle, will be the Russian Soyuz rocket. The two labs will be attached to the Universal Docking Module, a Russian element that provides a five-port node for additional Russian modules and vehicles. This module in turn will be attached to the Service Module and perform the same functions as the U.S. nodes. The Universal Docking Module will permit pressurized passage among the three facilities, as well as between Soyuz TM, Progress M1 and other Russian spacecraft. Personnel in the Russian Research Modules also will have direct access to the Docking Compartment through the Universal Docking Module.

The Russians have cancelled the Universal Docking Module and will replace it with a design modified from the FGB-2 backup spacecraft, which already is 80% complete.