Business Models have received attention, both from academia and from the market, especially since 2000, when the amount of research has grown exponentially. During the Covid-19 pandemic, the importance of this tool intensified, especially for the service sector, which was the most impacted during this period. However, there is no agreement among researchers on the concepts, elements, and methods of modeling business models. Given these two facts, the purpose of this article is to present the structure of the Business Model Service Area (BMSA) of an engineering office specialized in structural calculations to assist in the decision-making process to optimize management. The BMSA made it possible to visualize the company as an organizational architecture and helps in the perception of possible improvements and decision-making.