MOUNTAINWORKS is an office for strategic and financial consultancy in area and real estate development. It was founded by Marijn Spoelstra in 2006. The office provides specialism in integrated plan development, development strategies and financial expertise. It follows an integrated approach of the three main elements of development processes: space (concept, masterplan, urban design, architecture), finance (market, program, feasibility, business plan) and process (commitment, politics, organization, legal). It is involved in numerous large and smaller size projects from the initial, conceptual phase onwards. Clients are municipalities, housing corporations, project developers, investors and other land and real estate owners.

MOUNTAINWORKS has an international network of collaborators which consist of architects and urban designers, process and project managers, lawyers and other experts.