Abstract Cities and urban agglomerations are particularly vulnerable to the expected impacts caused by climate change. A building-resolving urban climate model as a tool for urban planning can contribute to prepare to these issues. However, currently available urban climate models do not correspond to the level of expertise of the various stakeholders in planning practice and their respective computing infrastructures. The German research program Urban Climate Under Change [UC]2 aims at the development, validation and application of a high-resolution and user-friendly urban climate model (PALM-4U) for entire cities. UseUClim, one of four joint research projects, reviews PALM-'s user-friendliness and practicality by applying the living lab approach. Living labs are platforms that gather all relevant stakeholders and, hereby, support a systematic user-science interaction. Both stakeholders from urban planning practice and model developers provide crucial input to the successful co-development of a scientifically-based and practicable urban climate model. Consequently, it is important that both contribute on an equal footing. To ensure this equality, UseUClim acts as a neutral intermediary between the two. Throughout the project it became apparent, that key success factors are clear and transparent communication flows as well as a common understanding of the project goals.