Space is rapidly changing. Every year, more numerous and more diverse actors embark on increasingly novel, innovative, and disruptive ventures in outer space. They are joining the more than 70 states, commercial companies, and international organizations currently operating over 1,500 satellites in Earth orbit. The prospects are bright; accessing and exploring outer space now require less capital investment, less time, and fewer people than ever before. However, this rapid pace of growth and change exists in a complex landscape of legal, regulatory, political, technical, and administrative issues. New actors in space face a steep learning curve and will stress existing institutions and governance frameworks. Additionally, the inherently difficult and fragile nature of the space environment means that accidents or mistakes in space might affect us all. In considering the great possibilities for growth, innovation, and in light of the myriad and interlinked challenges new space activities will confront, the Secure World Foundation offers this Handbook for New Actors in Space in the hopes that it will assist all aspiring new entrants - whether governmental or non-governmental - in planning and conducting space activities in a safe and sustainable manner.