Phase 3 completes the assembly and provides six-person crew permanent habitation, mature operations, and full international science capability. Canada, Japan, and participating European countries will add their remaining elements to the station. The many systems designed to perform remote assembly tasks will get a full workout attaching modules, truss segments, and solar arrays.

When complete, ISS will comprise 43,000 cubic feet of living and working space, in addition to outside surface area available for research. Phase 3 includes 29 Shuttle flights, beginning with delivery of the Mobile Transporter in May 1999 and concluding with U.S. Habitation module outfitting in June 2002.

Four solar arrays are added to Russian power/control mast providing additional Russian power. The JEM Module is delivered and activated and the U.S. Centrifuge Module is attached to Node 2.

The fourth U.S. truss-based photovoltaic module is delivered, completing the major power system elements. The last flight of Phase 3 completes outfitting of the U.S. Habitation module.