Section 3.3 was interesting to describe the basic agency problem that occurs at the inception of PPP projects. Those projects are typically long term projects which might cover 20 to 35 years. Over a long lasting project where the quality of durable assets and infrastructures may significantly depreciate, an important issue concerns the extent to which contractors are willing to invest to improve the stock of existing infrastructure in the longrun or whether they prefer to choose management strategies that maintain costs low in the short-run.