  This paper, framed in a vast investigation, describes the application of
techniques and methodologies in Organizational Engineering connected to the
associated risk to the processes developed in an Emergency Service of an
important Portuguese Hospital. The transactions performed in an emergency
service and the consequent risk identification (negative behaviour associated
to those transactions) is done based on static and dynamic models, developed
during the business modelling. Any non-trivial system is better portrayed
trough a small number of reasonably independent models. From this point of view
it is important to look at the systems from a "micro" perspective, which allows
us to analyse the system at the transaction level. All processes have some
associated risk (inherent risk). Its identification will be decisive for future
analysis and for the consequent decision over the need, or not, to study
internal control mechanisms. This decision will depend on the risk level that
the organization considers acceptable.
