CSCW systems are widely used for group activities in different organizations and setups. This study briefly describes the existing classifications of CSCW systems and their shortcomings. These existing classifications are helpful to categorize systems based on a general set of CSCW characteristics but do not provide any guidance towards system design and evaluation. After literature review of ACM CSCW conference (1986-2010), a new classification is proposed to categorize CSCW systems on the basis of domains. This proposed classification may help researchers to come up with more effective design and evaluation methods for CSCW systems. © Maxwell Scientific Organization, 2011.