Numerous scoring systems are available for various particular situations. Some clinicians consider scores as mandatory for daily clinical decision making, while others see them only as additional work with no proven benefit except for scientific aspects. Although scoring systems have their limitations, they can also be of value. This article provides an overview of existing systems used in emergency and intensive care medicine. The specific aims of different scoring systems are discussed and evaluated for the areas of disease classification, monitoring of individual patients and applications to individual decisions, quality assurance (comparison of patient groups and therapies), economic evaluation and global triage decisions. Despite the additional workload it is concluded that scoring systems are of proven benefit for classification of the degree of severity of a disease process, quality assurance, and better assessment of costs containment. These instruments will become increasingly important in our current discussion on changes in health care systems.