Vacuum cleaners suck, OK ! If we ignore the Americanism in this statement, we may think of Mr Dyson and his inestimable rethink of the vacuum cleaner. His design of a cyclone based cleaner was not only an engineering success but also a phenomenal business success. Mr Dyson is the archetypal Commercial Engineer. He combines successful design and engineering innovation with shrewd and effective business acumen. It is not difficult to think of examples where the two did not go hand-in-hand, where a good engineering approach was not married to a sound business approach. Now, Mr Dyson is a man of exceptional talent and arguably his achievements would not be more than of passing (largely technical) interest to the vast majority of professional engineers who happily spend their working lives working for a company believing it is for others to make sure that the business is a commercial success. That is, after all, what the other functions are for and very few professional engineers actually have the chance, la Mr Dyson, to set up their own company to exploit a design of their own creation. This may sound unfairly dismissive, but there are many engineers who hold to the view that provided they do their bit right then the business is bound to be a success, if only the other functions can manage not to mess things up!