Whom is this book intended for? It is for those new to the use and abuse of centrifugal pumps. It is also for those whose involvement with pumps is so occasional, that they need a reminder of the basics. I hope its content can help avoid just some of the problems I have seen or been involved with over the years. Modern centrifugal pumps are not complex machines. Usually they consist of a few castings, mouldings, or pressings that are pierced by a few wrought or turned components. Evidently, they are one of the ubiquitous machines, being comparable in numbers to the electric motor and the internal combustion engine.