The purpose of this report is to provide recommendations for actions Ukraine could take to implement large-scale installation of IHSs as part of comprehensive district heating reform. The report discusses the importance of IHS in the district heating sector, then presents several case studies of approaches that European countries have taken to facilitate large-scale IHS installation in multi-apartment buildings. These case studies focus on the ownership and financing of IHS, as there are different models for how this can be done (the DH company can make the investments and recover the costs through the tariff, or building residents can make the investments themselves). They also include details on the approval process and technical specifications, as these can add additional barriers and time to the installation process.