This study aims to provide an increased understanding of sustainability in general and recycling as well as re-use in particular. The study revolves around a literature study, a case study and an interview study. The literature study paints a background, the interview study provides a situational picture and the case study an illustration of possible environmental savings. In the background, the global goals are highlighted together with the Sustainable Development Goals (Agenda 2030), as well as how these can be linked to the EU's taxonomy. The taxonomy provides certain requirements, which if met can provide beneficial financing. The taxonomy can be seen as a tool to prioritize sustainable development. After this, the work narrows to Sweden's own goals and ambitions. One way to achieve these goals is to reduce the construction and real estate sector's climate impact. One way forward to do this is to increase the progression on recycling and re-use of building materials, as well as building parts. The literature study presents a method for a re-use inventory. Also, how the work to promote re-using can look like in the various stages of construction. In the interview study, relevant actors are given space to give their views on issues concerning challenges, costs, collaborations, and materials within the framework of sustainability, re-using and recycling. The materials that the study examines are selected with the reference object in mind. The parts studied are the building’s facade and frame, since these are where the large volumes of material lie. The facade of the reference object consists of brick and the frame is of concrete. A background and description of the properties of these materials are reported. Under the calculation part, the volumes of the reference object and its CO2-eq emissions are reported in kg. A comparison is made between a scenario without recycled and re-used material and a scenario with recycled and re-used material. Everything is ended with results, discussion, and conclusion. The results from the literature, case and interview studies indicate that re-use and recycling lead to environmental benefits, but that the CO2-e savings vary greatly depending on the material. A possible explanation for this variation is provided under the discussion section. The results also show that sustainability is something that all respondents work actively with, albeit in different ways based on their different professional roles. The study is directed towards (i) Recycling of a cast-in-place concrete frame and (ii) Re-using of a brick facade.