Someone is passing a building site (maybe an ordinary member of the public, maybe a famous celebrity or politician) and a brick slips off the scaffolding and falls on her head! Who does she sue for the injury and ruined hat (assuming that she is alive to take court action)? The bricklayer, bricklaying firm, contractor, scaffolding firm, architect, quantity surveyor, employer and more could all have had a hand in the incident: