Chaired by Lord Hardie, the probe has cost the taxpayer more than £13m. and has amazingly taken nine years to come to a conclusion.
It concludes failings by the City of Edinburgh Council and its arm's-length companies were to blame for the delays.Much criticism centres on the arm's-length company in charge of the tram project known as Tie.
The probe has highlighted considerable oversight, management and strategic mistakes by Tie, the City of Edinburgh Council and Scottish Ministers.
The report also highlights the failure of Tie to work collaboratively with the council and others including, in particular, Parsons Brinckerhoff (PB) and BSC, a consortium of Bilfinger Berger, Siemens and Spanish tram builder Construcciones y Auxiliar de Ferrocarriles (CAF), as well as a delay with production of design due to poor performance by Parsons Brinckerhoff and failure by tie and BSC to manage the design contract effectively.
The report also sets out 24 recommendations for the consideration of Scottish Ministers, including considering whether there is a requirement for new legislation to allow for civil and criminal sanctions against relevant individuals or companies who knowingly submit reports that include false statements to councillors.
The final cost of the tram project, according to the inquiry, is £835.7m, whilst the previously reported cost of £776.7m was very much an underestimate. The figures include the purchase of sufficient trams to run the original planned route between the airport and Newhaven.