The Stimson Center’s Space Security Program has released Stimson Report #69: “No Harmful Interference with Space Objects: The Key to Confidence Building.” This report, authored by Research Associate Sam Black, examines the concept of no harmful interference with satellites, and argues that it is the key to a sustainable code of conduct for responsible space-faring nations. Other vital elements of a code of conduct, such as debris mitigation or space traffic management, could be rendered moot if states don’t pledge to refrain from interfering with space objects. Banning harmful interference could also be a vital element of other broad space security strategies.