Basically, a few large modules would need to be carried to a location of your choice to setup a space centre. Let's say you put one on Minmus, here would be the benefits: -Ability to take off without the gravity or air resistance of Kerbin -Some parts could be made cheaper, in the event limited budgets are introduced due to the natural vacuum and low gravity. Good-quality solar panels for example, would need to be made in an artificial vacuum on Kerbin, which costs more than taking advantage of a natural vacuum on say Minmus -perhaps it could be used for repairs and refueling for ships on their way back to Kerbin, or on their way to another destination such as Eve Say you put one on Pol: -All the benefits of the Minmus base -Convenient when exploring other moons of Jool -A ship on it's way to Eeloo can stop for refueling or repair In order to avoid making the game too easy, these will be big, heavy modules which provide no benefits in the way of fuel or boosters (unless you count them being space to attach these things). They may even need to be brought one at a time. They will also need to be in the same general area as each other. Multiple modules should be needed to create a single building. Example of modules that could be required: http://pastebay.com/1278800