Mr T. N. Akroyd (Vice-president): Dr. Lewsley has touched on a matter that has been exercising the minds of many engineers for some time, i.e. professional negligence. I hope, however, that we do not become too morbid over the subject. There is a world of difference between showing a lively interest and a morbid interest because the audience here tonight is composed mainly of ‘doers’ or performers. As doers, if you have a morbid interest in this subject you will stop ‘doing’ and that will be the end of your raison d’etre. There is a world of difference between ‘doers’ and ‘advisers’ because advisers like a situation that is ossified, so that the facts do not change; they can then venture an opinion, 3 months later, on what you should have done at the time, if you had had the benefit of their advice. So there is a problem for the entrepreneur, a problem for the structural engineer, and a problem for the contractor. You have to act now; that usually means you need a clear grasp of the principles involved if you are to act rationally.