Abstract
Mankind has set foot on the Moon over three decades ago. Ever since then, NASA and other space agencies have planned to build an outpost on the Moon for changing reasons. Was it to show the technical advances of the US during the Cold War at first, today's reasons for a base on the Moon are more practical: Astronomy, Mining or Tourism are possible arguments for a human presence on Earth's only natural satellite. This paper summarizes environmental issues and other boundary conditions, a classification of structural concepts being considered for the Moon and challenges for future research. Some preliminary considerations on a lunar design are also presented.