Students for Sensible Drug Policy
Students for Sensible Drug Policy (or SSDP) is Columbia's branch of one of the largest college drug reform organizations. They hew to an aggressive but professional image -- think more "harm reduction" and "drug education" than legalization.
As the group's President in 2010-2011, Katharine Celentano turned SSDP from a small group to a prominent force on campus and in the SSDP national organization. She was subsequently elected to their national board.
They claim credit for updating the Good Samaritan policies at Columbia and Barnard[1].