The slow burn collapse of Carillion had been flagged for months since the company issued a profits warning last July, delaying its half year results. By September the relatively new group finance director, appointed in January 2017, had left the company and a change of chief financial officer and shakeup at the top of the company was seen as a final attempt to get the operation back on a level financial footing.

In reality, the business model was looking increasingly unworkable as margins were so tight and government contract wins were based on subcontracting the majority of work, undermining profitability further.