CSSR may refer to: Czechoslovak Socialist Republic (Czech and Slovak: ČSSR), onetime name of Czechoslovakia Climate Science Special Report, Volume 1 of the Fourth National Climate Assessment (NCA4) 2017/2018 Canadian Society for the Study of Religion Canadian Society for the Study of Rhetoric Center for the Study of Science and Religion, a center inside The Earth Institute at Columbia University Congregatio Sanctissimi Redemptoris, Latin name of the Congregation of the Most Holy Redeemer, abbreviated to C.Ss.R Council with Social Services Responsibilities, part of the UK Healthcare Commission Centre for Social Studies and Reforms (CSSR), based in Cochin, Kerala, India Call setup success rate, a term used in telecommunications denoting the percentage of the attempts to make a call which result in a connection to the dialed number Conservative Site-specific recombination