As a result of the Paris Agreement, Sweden established a climate goal in 2017, aiming for the country to be climate neutral by 2045. In 2019, the Swedish construction and civil engineering sector accounted for nearly 21 percent of domestic greenhouse gas emissions. This thesis aims to increase knowledge about how municipalities act through requirement-setting to achieve the goal of a climate-neutral construction and civil engineering sector by 2045. The study, conducted within the framework of the thesis, was based on the survey "Miljöbästa kommun 2022," where two questions addressed requirement-setting as a landowner and as a developer: 1. "Does the municipality set specific environmental and climate requirements during land allocations, transfers/leasing of land for residential construction?" 2. "As of January 1, 2022, developers are required to establish a climate declaration when constructing a building. Does the municipality, in its role as a developer, set threshold values with maximum emissions of greenhouse gases from buildings being constructed?" The survey revealed whether a responding municipality set requirements in one or both of these roles (a total of 81 responding municipalities answered yes) but did not specify how the requirements were formulated or how municipalities applied them. Through a literature review, an initial survey (targeted at the 81 municipalities from Klimatbästa kommun 2022; response rate 32/81), and subsequent interviews with twelve of the responding municipalities, the goal of the thesis has been to closely examine how municipalities set requirements as landowners and developers. The results from the thesis conducted in the fall of 2022 show that the municipalities in the study have high ambitions and sustainability goals to achieve climate neutrality by 2045, and that requirement-setting is an instrument in this effort. However, the municipalities face challenges such as legislation regarding municipal-specific requirements, lack of resources, and competence in the area. In their role as landowners, municipalities tend to use "relative improvements" by presenting desired outcomes and discussing with contractors how these can be achieved. Challenges such as the legal framework and lack of competence, however, affect municipalities' ability to effectively set requirements and achieve their goals. As developers, municipalities have varying approaches to setting requirements, with some using detailed requirements and others preferring functional requirements. This depends partly on the municipalities' resources and level of knowledge, but also on their ambitions and willingness to transition. 3The study indicates that the approach of municipalities varies depending on whether they act as landowners or developers. As landowners, municipalities have a unique opportunity to influence the development of land areas by setting requirements during land allocations. These requirements can vary and range from allocation criteria to improvement requirements and information requests. It is also common for municipalities to use other strategies to promote sustainable urban development, such as emphasizing sustainability ambitions without specifying detailed requirements. On the other hand, when municipalities act as developers, they usually implement specific requirements to achieve overarching climate goals or sustainability strategies. By using environmental certification systems and setting limits, municipalities can actively contribute to reducing the climate impact of construction projects and promoting more sustainable development. It emerged from the municipalities that, regardless of their role, they actively work with these types of requirements as all municipalities strive for a climate-neutral construction and civil engineering sector by 2045, in line with the Paris Agreement.