Job promotion is an important issue for employees' professional development. Our research aims to explore promotion systems for building engineers, used by small and medium construction companies in Castilla-La Mancha Autonomous Community We also aim at analyzing the influence of promotion on their job satisfaction. This paper draws on qualitative data comprising semi-structured interviews with 34 building engineers working as site managers for construction companies. Findings reveal that promotion is related, among other factors, to company size, site volume, qualifications, seniority or results. Additionally when promotion initiatives exist their influence on job satisfaction is positive, negative or neutral, while when they don't exist the effect is negative or neutral.