It may be argued that either approach leads to a consideration of the entire problem, so that it is of no great significance which way the organization is viewed. Certainly it makes this very important practical difference: those who work from the top down must guard themselves from the danger of sacrificing the effectiveness of the individual services in their zeal to achieve a model structure at the top, while those who start from, must guard themselves from the danger of thwarting co-ordination in their eagerness to develop effective individual services.