The Sustainable Development Goals (SDGs) represent a central framework for guiding sustainable urban development. However, it is not clear how and where SDG 11 (Sustainable Cities and Communities) is being implemented, and how such implementation might be improved. We investigate this subject by analyzing United Nations (UN) SDG Good Practices data from 2018 to 2021, using content analysis, classification, and descriptive statistics. The resulting analysis and classification is new in this field. We applied five criteria to the 336 SDG 11 responses: (1) geography; (2) actors; (3) progress toward targets; (4) areas of implementation; and (5) scale of action. Overall, 86 of the 193 countries that adopted the 2030 Agenda submitted at least one SDG 11 good practice. Thirty-three countries contributed 73.8% of the total, and most developing countries did not make submissions. A very small number of responses (between 2.6 and 9.1%) addressed equity-related targets. Good practices from developed countries were usually more technology-oriented and system-forming; developing countries typically focused on issues of day-to-day concern. This analysis points to the need for better and more systematic reporting on SDG 11 implementation, a more active public sector role in SDG implementation and reporting, more focus on dimensions related to social equity, and better formulation of urban sustainability targets and indicators.