Innovation is a necessity in a changing world. But what kind of innovation? 'Sustaining innovation' props up and temporarily fixes structures and processes that are failing-but does little for the longer term. 'Disruptive innovation' shakes things up in a way that can be welcome in the commercial sector, but is seldom wanted elsewhere. Typically, disruptive initiatives offer only short term impact or are eventually 'mainstreamed' to help sustain existing...