United States

- truss structures that provide the ISS framework;

- four pairs of large solar arrays;

- three nodes with ports for spacecraft and for passage to other ISS elements;

- airlock that accommodates American and Russian spacesuits;

- the American laboratory (Destiny);

- habitation and centrifuge accommodation modules;

- power, communications and data services;

-thermal control, environmental control and life support health.

Russia

- two research modules;

- service module with its own life support and habitation systems;

- science power platform that supplies about 20 kilowatts of electrical power;

- logistics transport using Progress vehicles and Soyuz spacecraft crew rotation.

ESA

- Columbus Orbital Facility (pressurized laboratory and external payload accommodations);

- logistics transport vehicles to be launched by the Ariane V.

Canada

- Mobile Servicing System (17-m-long robotic arm and with a smaller manipulator attachment;

- a Mobile Remote Servicer Base to allow the robotic arm to travel along the truss.

Japan

- on-orbit facility (pressurized laboratory, Logistics Module, and attached facility exposed to the vacuum of space serviced by a robotic arm;

- logistics resupply using the H-2 launch vehicle.

Brazil

-a pallet to house external payloads, unpressurized logistics carriers, and an Earth observation facility.

The International Space Station is an unprecedented achievement in global human endeavors to conceive, plan, build, operate, and utilize a research platform in space. With the assembly of the space station at its completion and the support of a full-time crew of six, a new era of utilization for research has begun.

The mission of the International Space Station is to enable long-term exploration of space and provide benefits to people on Earth. With six state-of-the-art laboratories, the Space Station will be the premiere research facility in space, four times larger and more capable than any previous space station. It is hoped that it will allow for advancements in medicine, technology and science. For example, studies in micro and hyper gravity will help researchers better understand its effects on humans and offer insight into how the human body works. Growing protein crystals in a space environment can help scientists create better treatment for numerous diseases that currently have no cure. In addition, the laboratories on the Space Station will allow for innovative space research projects to improve our understanding of the Earth's environment and the universe in which we live.

The Space Station will also serve as the gateway to new frontiers in human space exploration, a place where we can learn how to live and work "off planet." It will allow for the study of long-term effects of weightlessness on the human body and as a test bed to understand what adjustments need to be made to current methods before astronauts are sent to Mars and beyond. In addition, it will allow for critical research in fluids, combustion, life support systems and the radiation environment, which is needed for future human space exploration.

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