Southwest Research Institute^® has assembled an international team of astronomers, biologists, and geologists to tackle fundamental scientific questions about life outside the Earth. This multidisciplinary collaboration, led by SwRI astrobiologist Dr. David Grinspoon, seeks to understand how habitable planets arise in the galaxy. The astrobiology team, known as the Southwest Astrobiology Center, has submitted a detailed proposal to NASA to join the NASA Astrobiology Institute. The diversity of the Southwest Astrobiology Center is such that a wide range of scientific investigative techniques are being employed. Massive computer models that simulate the formation of planetary systems and the climates of rocky planets allow the team to theoretically predict the conditions on planets around other stars. Field campaigns to explore life in extreme environments, such as in underground cave systems and in the tiny particles of a cloud illuminate the issue of what is required on a planet for a 'habitable' environment. Laboratory studies and astronomical observations provide key data for understanding the environments in which habitable planets are likely to form. Future NASA missions, such as the Terrestrial Planet Finder, will return remote sensing data on the nature of these planets, and the Southwest Astrobiology Center will provide a firm foundation for understanding these new worlds.