Smart cities are proposed as a solution for problems of urbanization. Technologies associated with smart cities involve the monitoring of human activities and resulting data streams. These technologies affect certain public values, which may be subject to change depending on their sociotechnical development. This paper presents a method that enables decision-makers to anticipate on this pattern of value change. This method uses two axes that allow a technology to be plotted in terms of different value-laden functions: a first axis in which projects are classified that collect either personal information or impersonal information; a second axis that classifies projects as to whether they collect data for the purpose of service or surveillance. For 37 sensor-based projects in the city of Rotterdam, it has been studied how projects may shift from one quadrant to another. These shifts inform decision-makers so they are better capable of anticipating undesirable impacts of technological developments.@en