Carillion is, or was, the second largest construction firm in the UK. It’s collapse on Monday 15 January 2017 was confirmed when the High Court ordered the compulsory liquidation of the various companies in the group. It employed 20,000 people and the projects of the business included the HS2 rail project, Battersea Power Station redevelopment, military contracts and the maintenance of schools, prisons and hospitals. So, what happens now?