This paper describes current work to undertake a market assessment of the potential for the application of Passive Downdraft Evaporative Cooling (PDEC) to new and existing buildings in Southern Europe. The work is carried out as part of a European funded ALTENER project focussing on solar and passive ventilation for urban buildings. PDEC is a technique that may potentially become a substitute for conventional air-conditioning. The technique avoids the need for ductwork, fans and suspended ceilings, and reduces the need for refrigerant based cooling. Hidden benefits include reduction in the overall height required for the building and consequent reduction in cladding costs. More obvious benefits include potential annual savings in energy and maintenance costs. PDEC is a design approach and it therefore needs to be explained and sold to building designers and building users. The project will include surveys of market barriers to the application of PDEC, and subsequent dissemination of the results to construction industry professionals, developers and facilities managers.