McKinsey share their thinking on the need to understand the psychology of change management through academic writings, existing publications and a review of several case studies. It is stated that four basic conditions must exist for employees to change their behaviour: a compelling story; role modelling; reinforcing and capacity building. In order for successful change practice, McKinsey advocate leaders must regard the irrational elements of human nature and their predictability – of which nine insights are uncovered and explained, to be considered against the four basic conditions.