Idea 17 - The 80:20 principle Businesses, like life, become so much easier to manage with a few basic principles you can rely on. Management theorists spend much time trying to pin them down, to formulate them in such a way that they will work again and again. But once you move away from the factory floor, where the laws of physics and statistics prevail, things become far less predictable. So it is with some relief that managers can turn to the '80:20 principle', knowing that it is almost entirely dependable. The 80:20 principle says that 20% of causes invariably produce 80% of the results, so 80% of what you achieve is due to 20% of the work you put in - and vice versa. It's that simple, but the implications, are many and various, for management and, so evangelists insist, for living itself. It began life as the Pareto principle, uncovered by Italian economist and sociologist Vilfredo Pareto in 1897. Studying the patterns of wealth in England, he realised