Business process- and decisions-modelling methodologies have developed largely independently and the existing lack of cross-discipline integration in the area of business modelling is not only counterproductive for future methodological advances, but also imposes unnecessary limits on the ability of the existing business modelling tools to adequately reflect the complex integrated nature of a business enterprise. This paper examines the relationship between business process-modelling methodology of Event- Driven Process Chains (EPCs) and a variety of decision-modelling methods originating from the field of Operations Research/ Management Science. A path towards integration of business process- and decision-modelling tools is proposed by enhancing the decision capabilities of EPCs with the aim of achieving a more comprehensive and flexible model of business enterprise and further development of both modelling methods.