Since 1972, the United Nations General Assembly has played an important, and often underappreciated, role in developing international legislation in response to terrorism. The Assembly has been central to the development of 19 international conventions dealing with terrorism. This chapter outlines the origins and main provisions of those conventions, as well as the other kinds of counter-terrorism strategies undertaken by the General Assembly. Both of these approaches link to the nearly complete, but stalled, UN effort to develop a comprehensive convention against international terrorism. At the core of all of these efforts is the difficulty inherent in attempting to find an agreed definition of terrorism. Although this remains a key stumbling block it should not detract from what the Assembly has achieved even though a comprehensive convention remains elusive.