Abstract. The aim of the contribution is to elaborate the digitalization of the construction process and of the management of the construction for both the organization of work activity and safety on the building site. The BIM methodology requires a digital implementation of construction through the creation of virtual models pertaining to the various professions involved. The CoSIM, acronym for Construction Site Information Modelling, is the application of BIM in the building site and where the federated model of the design phase materializes. The goal of the methodology developed is to obtain an elevated quality standard of the project, while trying to maximise costs and time as much as possible to favour an increase in the level of safety and security on the building site. The BSS, Building Site Safety, will allow a maximization of the safety design, not only by graphically depicting work activity but also forming a digital system for the documentation of the building site. To support this, the model is integrated with a simple plug-in which contains a library of objects to use for the designing and planning of safety on site, from general information to state of emergency warning. Thanks to the combination of the CoSIM and the BSS we can have a reduction of the variant, a reduction of time and costs due to an improved planning of work activity and allows the worker to be aware of all the modalities of procedure before entering the building site.