This article discusses how CIAM (Congrès Internationaux d’Architecture Moderne) influenced Dutch housing and urban planning. It starts by looking at programs and policies of the 1920s and 1930s Dutch housing design, and the way in which the new ideas of CIAM were there incorporated. In this history, the design of the AUP (Algemeen Uitbreidingsplan Amsterdam, or the General Extension Plan) is crucial, marking the transition into a new spatial model for large scale housing areas. CIAM thinking and its successor, TEAM X, strongly influenced the idea of the social-cultural city before and directly after WWII. This becomes evident in the urban extensions of Amsterdam and Rotterdam. This practice influenced urban planning and housing design and culminated during the 1970s in the design of the Bijlmermeer. Though legendary and still detectable in the urban developments of Amsterdam and Rotterdam, CIAM thinking came forward as both visionary and problematic. This article will trace the CIAM history in these two cities to depict concepts of innovation, but also continuities in modern housing design and planning practices by focusing on spatial models, typo-morphological transformations, and ideals vis- à-vis the urban public realm. In addition to relevant writings, typo-morphological maps, drawings and street photography also serve as tools of analysis and interpretation. The article will conclude with some future perspectives regarding the relationship between the CIAM legacy and contemporary urban issues.