108. PPP projects are capital intensive, tend to be long-term (20-30 years), and are generally perceived as risky, especially during the construction phase. These challenges and the realities of the MENA-region, mean that private-sector infrastructure financing can be difficult to secure. For any given project, private investment generally comes from two sources, foreign or domestic. The barriers to both foreign and domestic investment in MENA-region PPPs are considered below.