The book deals with the study and design of a multi-agent simulation model based on a concurrent process environment. The aim is to design a distributed simulation model under a concurrent process language, in particular Erlang, and to analyze its feasibility, with a view to achieving a higher level of complexity. Our approach is to show that this model can be adapted to the types of applications that enable us to monitor the evolution of a fish population in space and time in the face of multiple environmental disturbances. The first is to propose a new multi-agent design model in this process environment. The second is to adapt the model to the application context, so that it can be validated with a real example. This work will be partly based on the model initiated in the Rapsodie project, which has shown certain limitations linked to a slow simulation speed and rapid saturation due to the cumbersome nature of the chosen simulation tool (Cormas).