Financialization, even contested, is a major focus of contemporary urban studies. The growing interest of institutional investors in real estate investments has been the subject of in-depth analyses that have suggested the need to critically examine their weight in contemporary urban production. Have investors become the new masters of the urban fabric, to the detriment of historical players such as property developers or local authorities ? This article informs the discussion by looking at developers at work and identifying how financial profitability calculations could have invaded their activities. Based on a qualitative survey conducted in France on practising or retired professionals, it shows that there has actually been a surprising degree of stability in professional practices over the past 50 years, even though the economic environment changed at the beginning of the 1990s. Since the origins of the property development sector in France, the real estate firms have had close ties with the financial industry and have been using financial instruments. This is why they were considered as ‘financial natives’, while employees at the operational level remain outside the scope of the colonization of organizations by financial quantifications. The specific nature of real estate work, particularly its political component means that decisions lower down in these companies cannot be guided solely by financial ratios. The extent of the changes triggered by the massive arrival of financial investments has not been as great as it may seem, since developers appear to have maintained most of their ability to influence contemporary urban governance.