**9. Conclusions and acknowledgement**

Prof. Carl Adam Petri wrote: "In order to apply net theory with success, a user of net theory can just rely on the fact that every net which he can specify explicitly (draw on paper) can be connected by a short (≤ 4) chain of net morphisms to the physical real world; your net is, in a very precise sense, physically implementable".

We have seen this quotation at the very beginning of this chapter. This chapter tries to make clear how to specify a net that is "in a very precise sense physically implementable". A successful application of net theory starts from a full understanding of the application problem. A well designed business process ((T,<), B ,C) leads to the discovery of workflow logic, case semantics and management pairs, a tree-layer model for workflow modeling.

Without theory, full understanding of application problems becomes hard. Well-structured business process ((T,<), B , C) starts from a clear distinction between business process and workflow, a clear distinction between business tasks and management tasks, and a clear distinction between transition synchronizations and place synchronizations. Business process and workflow are not synonym of each other.

A full understanding of application problems and a good grasp of theories in Petri nets that build a road to success.

The author is grateful to the editors of this book. It is a great honor to me as well as a good chance for me to exchange ideas on Petri nets with friends outside my country.
