There have been relatively few studies on the impact of private sector participation on infrastructure operation. Nonetheless, available evidence suggests that private sector participation can improve service delivery and management, compared to government-run infrastructure services.
For example, a comprehensive 2009 study by the World Bank [#109] analyzed the effect of introducing private sector participation through concessions or full privatization of utilities. The study used econometric analysis to assess performance of over 1,200 water and electricity utilities, in 71 developing and transition countries. The study found significant efficiency gains when private sector participation was introduced- including reduced water losses and increased staff efficiency. These gains came alongside improvements in service delivery, with increased coverage and daily hours of service. A study by Marin of private participation in urban water utilities, also in 2009, analyzed the performance of 65 large water PPPs and similar contracts (including management contracts) in developing countries worldwide. Marin also found that introducing a private operator consistently improved operational efficiency and service quality [#180].