CSSD may refer to: Royal Central School of Speech and Drama, London, England Central sterile services department, an integrated place in health-care facilities that performs sterilization of medical devices Cloneproof Schwartz Sequential Dropping, a single-winner election method Computer Supported Spiritual Development, a field of study related to computer-supported collaboration Czech Social Democratic Party, Česká strana sociálně demokratická, ČSSD Department of Children, Seniors and Social Development (Newfoundland and Labrador), child protection agency in Newfoundland, Canada