While space capabilities were once concentrated among a handful of leading powers, an increasingly large number of states have gained access to them. As of 2007, 58 countries possessed dedicated civil space programs, 44 countries had placed nationally owned satellites into orbit, and 9 countries had achieved domestic space launch capabilities. To date, however, no systematic inquiries have ever been conducted into which countries acquire space capabilities and why. Within this paper, I develop an explanatory account that explores the capacity-based factors and political motivations that influence countries' acquisition of space capabilities. I test my hypotheses via a quantitative analysis of the factors affecting 143 countries' acquisition of civil space programs, satellite capabilities, and space launch capabilities from 1950 to 2002. My findings shed new light on the primary causes of the proliferation of civil space capabilities and yield a number of important policy implications.