Public problems and controversies usually refer to two traditions of social sciences. The first one focuses on processes through which private issues transform into collective concerns and raise interest among politicians. Its most classical case studies include civil rights or environmental issues. The second tradition refers to conflicts related to science and technology in society. It underlines the role of scientific reasoning on highly debated topics such as nuclear waste or big data. I argue that the two research perspectives, as different as they are, could gain in analytical depth and precision from one another. My paper is an attempt to illustrate this through some research projects developed over the past ten years on traffic safety and smart cities in France and the United States.