CARLOS FERNÁNDEZ CASADO S.L. OFICINA DE PROYECTOS (CFCSL) is an independent civil and structural engineering consulting company based in Madrid (Spain) devoted to the research, study, development and supervision of structural engineering projects.

CFCSL provides highly specialized services that include feasibility studies, preliminary and detailed design, independent checking and construction supervision of any kind of structures.
The company has designed and supervised many major and high-technology structures all over the world, particularly bridges some of which hold world records.

CFCSL employs highly trained and specialized engineers. The firm has gained a worldwide reputation since its foundation in 1966 for its contribution to the development of structural engineering technology and for its innovative and original structures.