A revolution in accepted views about the role and design of macroeconomic policy for developed economies occurred in the last quarter of the 20th century. The essential Keynesian idea that economies should be actively managed to achieve high levels of output and employment was largely abandoned in favour of the different, much less ambitious view that policy should be directed to achieving monetary stability – principally price stability – in the belief that stability will promote growth and prosperity more securely, if less deliberately, than Keynesian intervention.