The aim of this article is to shed light on how ongoing structural change towards the global digital economy condition urban economic development. Discussion starts with a brief reference to the growth machine thesis and its emphasis on the interests of local land and real estate owners. This theory serves as a contrasting point for the second element of our framework, the platform economy, which brings digital platforms and the transnational capitalist class into the picture. The transition from the urban growth machines of the industrial age to the digital growth platforms of the information age imply a radical change in the context of urban economic development. On this basis, we discuss cities’ need to adjust their growth strategies to the conditions of the emerging platform economy. Our illustrative case is the capital region of Finland. We interviewed officials and experts who hold key positions in the design of economic development policy in the three largest cities of this area. The empirical results show that the platform economy is rather vaguely conceptualized, and its challenges are ambiguously addressed. Cities have, however, started to adopt platform and ecosystem thinking in their strategies and established urban innovation platforms, talent and start-up attraction programs, and open data initiatives that reflect the gradual adoption of platform logic in urban economic development.