Organisation structures have been planned and changed—or not planned and not changed—for as long as human beings have combined their efforts towards common goals. Organising means, in the words of A. A. Milne's Rabbit, “what you do to a search when you dont't all look in the same place at once”. The mode of organising collective work exercises a considerable influence on how it is performed and its overall effectiveness. Too often in the past organisational change has proved too little or too late. The escalating size of organisations, and complexity and interdependence of the environments in which they operate, render the planning and monitoring of their structures a managerial priority of increasingly urgent importance. In the future, firms are likely, either to develop, preferably by design, or to die. They may well be more or less successful in direct relation to whether, or how, they organise, not least to organise.