In addition to considering fiscal exposure on a project-by-project basis, some governments introduce targets or rules limiting aggregate exposure. Given the difficulties in deciding whether a particular PPP commitment is affordable, limits on aggregate exposure can be a helpful way to ensure the government’s total exposure to PPP costs and risks remain within manageable limits. Examples of PPP fiscal limits are presented in box 2.22.
BOX 2.22: PPP fiscal limits
However, creating PPP specific limits distinct from other limits on public expenditure can simply create incentives for agencies to choose public procurement over PPP even when PPP would provide better Value for Money.
An alternative, therefore, is to incorporate limits on PPP commitments within other fiscal targets. For example, some governments introduce targets or limits on public debt. Some types of PPP commitment may be included within measurements of public debt, following international norms or national rules. In such cases, an appropriate approach could be to establish a limit on “debt plus PPP commitments”. In any control on total PPP exposure, a difficult issue will be whether to include contingent liabilities, and if so, how to value them.
When aggregate exposure is limited, each PPP will have to be tested against such overall limits, under the respective appraisal exercises as part of the approval process (see chapter 4.12).
 President of Peru (2008) Legislative Decree No. 1012.
 Irwin and Mokdad (2010) Managing Contingent Liabilities in Public-Private Partnerships: Practice in Australia, Chile, and South Africa. World Bank/Public Private Infrastructure Advisory Facility.
 Brazil, Presidency of the Republic (2004) Law 11079 ("Federal PPP Law").