Purpose Shrinking population can have significant negative impacts on the social and economic fabric of a city. This paper aims to understand different urban transportation policies to respond to population decline in shrinking cities by examining two case studies of urban interventions in mid-size cities in Japan. Design/methodology/approach The paper analyzes the implementation of sustainable mobility strategies in the urban transport sector in the Japanese cities of Toyama and Kanazawa, which risk having their populations significantly reduced in the next decades. The analysis is based on case study research that uses the data and information collected through desk and field research. Interviews with local actors, as well as published policy and academic documents on the case studies provided critical data and information to analyze the case studies. Findings Both cities have tried to make urban mobility more sustainable via different strategies. Toyama used more structural changes, called the "sticks and dumplings" approach, having land use incentives and the Light Rail Transit reinforced by bus routes as the backbone of its strategy. Kanazawa relied on a city center revitalization plan to densify residential use in the city center. Practical implications More structural interventions are necessary to change the declining of shrinking cities, mitigating some of the negative effects. City administrations need to have clear policy priorities and should not allocate their limited resources to competing policy agendas. Originality/value The study is unique as it is one of the first efforts to analyze urban transportation interventions in shrinking cities in Japan.