The fundamental principles are famously (although not for the first time — see R v Brent London BC ex parte Gunning [1985] 84 LGR 168) set out by Lord Woolf MR (as he then was) in R v North and East Devon Health Authority, ex parte Coughlan [2001] QB 213, [2000] 3 All ER 850, at [108] as follows: whether or not consultation is a legal requirement, if it is
embarked upon it must be carried out properly; to be proper, consultation must be undertaken at a time when proposals are still at a formative
stage; it must include sufficient reasons for particular proposals to allow those consulted to give intelligent consideration and an intelligent response; adequate time must be given for this purpose; and the product of consultation must be conscientiously taken into account when the ultimate decision is taken.