The paper presents the results of a multiple case study analyzing how leading European smart cities implement data ethics within their digital strategies and manage algorithmic discrimination risks. The case study compares the ethical strategies of Barcelona, Hamburg and Darmstadt, selected for their leadership in digitalization, their data ethics strategies, and their pioneering role as smart cities. Specifically, it examines how data ethics are integrated into the cities’ digital strategies and how algorithmic discrimination risks are addressed. It also discusses which stakeholders need to be sensitized to the risks of algorithmic discrimination and shows what leading smart cities are doing to reach these stakeholders. The case study included an analysis of publicly available information on the digital strategies and their implementation in the three selected smart cities, as well as interviews with experts involved in urban digitalization and the implementation of smart city strategies. Based on these findings, recommendations on how to integrate ethical issues into smart city strategies were derived, which can serve as guidelines for cities striving for responsible and inclusive digital strategies.