In a competitive environment and with constantly changing lifestyle and consumption habits, the hotel industry offer, and the services built around accommodation and catering as we know its today, do not guaranty the attractiveness, or the profitability, that is needed for this sector to remain sustainable. The modeling of a "new" hotel industry is necessary to meet customer expectations while taking into account the costs and operating constraints, particularly the "hotel industry service" playing a key role in the production and distribution processes of the service as well as in the quality perceived by the customer. The determinants of the hotel operational performance have evolved in different cycles turning the "modern" into "traditional".This thesis begins with the exploration of these developments in mid-ranged hotels in France through a field study conducted in twelve hotels and the headquarters of the AccorHotels group in France. This step, questioning the future of mid-ranged hotels in France, raised research questions wondering about the importance of the staff in the production of mid-ranged hotels products and services in our society, and more broadly, the importance of the human capital (in the microeconomic meaning) in the hotel industry.We decided to explore the links between staff and the hotel operational performance. This performance is composed of economic results, the quality perceived by the customers as well as parameters related to the context of the hotels. Based on an in-depth study of all the methodologies and measures of human capital, we chose to measure it through employee engagement at work, using a sample of 146 mid-range hotels (representing 3740 employees) of the AccorHotels group in France. We also measured, for each hotel, a set of context data (size, location, customer mix, level of digitization, renovations...), the operating result (Earnings Before Interest Taxes), the number of business per room available (RevPar) and a measure of the quality perceived by customers (Reputation Performance Score).This thesis shows the links between the operating result per room, the quality perceived by customers and the commitment of employees to work. We will develop their respective antecedents as well as the nature of their cross-statistical relationships.This thesis prooves that as a significant precedent of the quality perceived by the customers (itself an antecedent of the operating result), the commitment of the collaborators into their work is instrumental in order to obtain a better performance for the mid-ranged hotels in France. To go further, the identification of a typology of hotels based on these links makes us able to obtain simultaneously a global and a segmented view of the mid-range hotel business in France and the role by type of hotels of staff in order to reach a higher performance.