Public-private partnerships (PPPs) are organizational forms involving public and private institutions and aiming at the provision of assets, goods, or services that, to a large extent, are relevant in terms of public interest. Alternatively, the same tasks (e.g., construction, operation, maintenance, financing) can be pursued by full-fledged public organizations. The nature of tasks and involved institutions (e.g., for-profit firms, non-governmental organizations (NGOs), governmental agencies) and the constraints shaping interactions among partners (e.g., contract or information incompleteness) determine different effects as regards the distribution of risks and payoffs among partners and allocative efficiency.