China's urbanization has avoided the expansion of slums despite the influx of rural migrants. What might explain this phenomenon? We argue that Chinese urbanization is driven by two tracks rooted in the country's land ownership: 1) a state-led track relying on land financing and expropriation, facilitated capital accumulation, infrastructure construction, and the provision of public goods; 2) an informal track based on collective land ownership and self-governance resulted in informal “urban villages” that provide affordable housing and services to migrants. China's urbanization underscores the credibility thesis, which posits that institutional form follows from function, as the urban villages – as informal settlements – fulfil a credible function in driving urbanization by accommodating the migrant population. However, Chinese urbanization is challenged by issues of sustainability and inclusiveness, and its current credibility might not last. In this context, local policy innovations may highlight possibilities to integrate the tracks and achieve a new type of urbanization by “formalization of the informal.” Put differently, the inclusion of that what is done into law, which should be critically distinguished from privatization through titling. At this point, one could consider the Credibility Scales and Intervention (CSI) Checklist, a “toolbox” of policy interventions predicated upon the credibility thesis.