nfrastructures, such as roads, railways, and water supply networks, require investment, upgrades and maintenance throughout their life-cycle. Often the funding of these through public budgets is considered insufficient. The deployment of private capital for infrastructure finance – public-private partnerships (PPP) – is seen as one solution. PPPs have also been regarded as a manifestation of neoliberal policies that comprise privatisation of public assets or transforming the assets into market-oriented entities. 

PPPs should be regarded neither as privatisations nor transformations, but primarily as projects where private investors invest their capital in the project asset, make commercial use of the asset and generate returns on their investment. The often politicised nature of PPPs calls for more holistic and objective tools to appraise PPPs that on one hand have a pure profit-motivated nature, and on the other hand are investments with significant socio-economic and environmental impacts. 

This thesis provides an integrated and holistic view on public-private partnership projects in terms of their distributional effects within the entire PPP ecosystem context. The result presented is an analytical framework: an integrated model that can be used as a ‘debate platform’ by the actors within the PPP ecosystem, so that the prerequisites to find where sharing of goals and risks make sense, and to bring fairness to the entire PPP project lifecycle. PPP projects are in fact business ecosystems that interact with the surrounding society and markets in a variety of ways. Therefore, the stakeholder view in PPP investments and business is crucial. The main beneficiaries of the model are the investors in PPP projects and the infrastructure managers and public financing bodies that may consider if a PPP is a viable option to realise a project. 

This thesis is built on three models: the PPP project model, the PPP ecosystem model, and the market model. The fourth model, the integrated model for infrastructure PPPs, is a synthesis of the other three models. Each article following this compendium details the corresponding model. The first article uses the first PPP road project in Finland as an empirical case and forms the base project model that shows a project’s cash flows and how project valuation is done, mainly focusing on two stakeholder segments: the investors and the state. The second article shows how an infrastructure PPP market is structured, thus distinguishing different market ‘layers’. It also analyses the returns of different infrastructures to their owners and discusses the PPP prospect in ownership and governance contexts using Finnish data sets from 2002-2009. All main infrastructures were covered by the analysis of this article. The third article on the PPP ecosystem model widens the project model and involves stakeholders from different market layers, resulting in a financial statement model for the entire ecosystem. The final article integrates the market layer and ecosystem views and hence it is named as the integrated model. 

The constructive and inductive process based on the four models allows the formulation of four main postulates that conclude this thesis: 1) PPPs revenue logic should rely mainly on market-based funding; 2) PPPs are risky with respect to their social sustainability, which is due to many potential and complex spill-over effects; 3) PPPs must also be considered as ecosystems, where the stakeholders are actors in the ecosystem with sometimes conflicting and sometimes coinciding interests; 4) it is more logical to draw market specific policies rather than PPP project policies. This type of integrated model has not been presented earlier, which is the main scientific contribution of this thesis. The practical contribution is that the model can be used as an instrument particularly at the early development stages of an infrastructure project to assess if both commercial and societal goals can be achieved with a PPP arrangement. The model requires further empirical testing and must be validated for usability in varying infrastructure PPP cases.