The image of public-to-private partnerships (PPPs) in relation to infrastructure took a hit a few years ago, but now they are back, and are much better for investors than before. 

That's the view of AMP Capital Head of Investment Strategy and Chief Economist Shane Oliver, who said that in the years leading up to the 2008 financial crisis, investor syndicates often had to over bid for infrastructure opportunities to get access to them, making it difficult in some cases to cover the costs and make the assets profitable once completed. 

“The model has improved substantially,” says Oliver. “It’s less focused on encouraging the private partners to excessively bid up the price for the underlying asset and we’ve ended up with a more sustainable model."