With the evolution of manned space flight has come a wealth of knowledge on supporting human life in the hostile environment of outer space. Each successive manned space program has built and improved upon the last, learning from the successes and failures experienced on each mission. As crew size, mission duration, and mission complexity have increased, the spacecraft environmental control and life support system (ECLSS) has been adapted and improved based on lessons learned from the past. The design of ECLSS for future manned missions beyond the space station must begin with a knowledge of past designs. This knowledge should come from the manned space programs of both the United States and the Soviet Union. The U.S. experience in space is well documented, providing many valuable lessons for future space travel. The Soviets have logged more time in space than all other spacefaring nations combined, yet their valuable experience is too often overlooked. As the political picture in the Soviet Union continues to change, more cooperation and information exchange should become possible with Soviet scientists and engineers. The U.S. and Soviet ECLSS design decisions from the past should take on equal importance when considering the design choices for future ECLSS.A summary of the ECLSS on U.S. manned spacecraft is presented in tabular form for Mercury, Gemini, Apollo, Skylab, Spacelab, the Space Shuttle Orbiter, and Space Station Freedom. A summary of the ECLSS on Soviet spacecraft is also presented, including Vostok, Voskhod, Soyuz, Salyut, the Buran Space Shuttle, and the Mir Space Station. This survey on spacecraft ECLSS was performed to gain insight into other spacecraft ECLSS designs.