Time and time again, managers have tried to flatten hierarchies, eliminate office politics, and quell interdepartmental rivalry - but to no avail. Why? The new science of evolutionary psychology argues that these managers are working against human nature - emotional and behavioural 'hardwiring' that is the legacy of our Stone Age ancestors. In this remarkable book, Nigel Nicholson explores evolutionary psychology's central tenets and its implications for business management. His insights into human instinct will intrigue and inform managers seeking to understand why people act the way they do in organisational settings. Evolutionary psychology also explores the dynamics of the human group. Clans on the Savannah Plain, for example, appear to have had no more than 150 members. The message for managers? People are likely to be most effective in small organisational units.