Abstract. One of the problem in business process reengineering is the identification and implementation of new workflow procedures for specific business processes, if they are not clearly defined. Analysis of unstructured (ad-hoc) activities cannot be based on traditional approaches using existing business procedures and expert knowledge. The method of business processes analysis in unstructured environments is presented in this paper. The creation of new business procedures is based on investigation of the communication acts, and application of similar workflow patterns. This method is useful in the earliest stages of business process reengineering. Preliminary analysis in ad-hoc area can be done for process identification, applying the existing knowledge baggage, reducing the analytical efforts, and creating the strong motivation for managers. Key words: business process analysis, business process reengineering, workflow, unstructured process, communication act, workflow definition, ...