A manageable model of reality is necessary in order to understand organization‟s components and their interrelationships (Perumpalath, 2005). Business process change involves changes in people, processes and technology (Indihar-Stemberger et al., 2003). Barjis (2008) maintains that “the recursive activities of adapt-change-improve would be a driving force for the 21st century enterprises” therefore business process modelling and simulation might be a crucial tool for assessing business processes.According to Perumpalath (2005), an organisation may be considered as a complex system comprised of functions, processes, resources, customers, suppliers etc.

Therefore organizations should look for ways how to diminish business risk. Increasing competition, growing customer requirements, shift of technologies and other rapid market changes push businesses into higher risk and may invoke serious consequences for them. (2004), Banks (2000), Greasley (2004) and other researchers and supports the findings with practical examples on how implementation of M&S has helped to improve business processing of huge transnational corporations. The article overviews and sums-up opinions of Chang and Makatsoris (2001), Johnson (2000), Brown et al. Thus, the aim of the article is to contrast main advantages and disadvantages of business process modelling and simulation, and to assess usage of M&S in planning of business processes.

Scholars describe many positive and negative aspects of applying modelling and simulation of business processes within the organisation. M&S allow visualisation, imitation of behaviour and forecasting of wide scope of business processes. Such tool might be timely and manageable modelling and simulation (M&S) of business processes. In the context of increasingly changing business environment, organizations need reliable tool for assessing and forecasting business processes. Jūratė Grikštaitė, Vilnius Gediminas Technical University, Lithuania Global Academic Society Journal: Social Science Insight, Vol. (2008) Business process modelling and simulation: advantages and disadvantages.

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