In Germany, public spending for buildings has decreased dramatically over more than a decade and has resulted in an enormous backlog of investments in public buildings, such as schools, prisons and hospitals. Due to a tight budget, the investment opportunities of public authorities are strictly limited and an improvement of this situation can not be expected in the near future. In order to be able to satisfy the needs for essential investments in public buildings, Public Private Partnerships (PPP) are becoming more and more popular in Germany. PPP aims to involve private sector parties in the provision of public services, which allows for comprising private knowledge and capital. It is expected that the amount of PPP projects will increase significantly over the next years, which consequently requires a large amount of capital from the private sector. For this reason, sponsors as well as institutional investors will play an important role in providing equity to the projects. However, both the public and the private sector lack experience in embedding investors into PPP projects. While substantial experience and research has led to standardisation on other PPP markets (e.g. United Kingdom), proficiency in Germany is still missing and makes further investigation in this field indispensable. After a short introduction to the development of public investments in Germany, the paper will outline the potential for PPP in the building sector and it will be derived, why the involvement of private investors is crucial for the future of PPP in Germany. From literature research and face-to-face interviews carried out with various participants in the PPP market, different kinds of investors on the German market will be identified and categorised. Interviews with PPP investors will give an insight into their evaluation of the German PPP market and illustrate their objectives and decision criteria. This will lead to conclusions on how the financial structure of PPPs can be improved and how different kinds of investors can best participate in German PPP projects.