This chapter provides a survey of existing approaches to discrete event behavior modeling. The comparison is based on the selected set of semantic elements useful for the major system life cycle activities, such as requirements engineering, analysis, system understanding, system design, and evolution. The semantic elements are identified in the observed approaches and illustrated with examples of models. The advantages of the semantic elements for the major system life cycle activities can be taken into account for the choice and for the design of behavior modeling approaches.The survey is based on a series of successful international workshops on behavior modeling run by the author and is enriched by the results of her research experience.