“Over the last 50 years, the ‘Marshmallow Test’ has become synonymous with temptation, willpower, and grit. Walter Mischel’s work permeates popular culture.” In a Q&A, Mischel discusses “what the [test] really captures, how schools can use his work to help problem students, why men like Tiger Woods and President Bill Clinton may have suffered ‘willpower fatigue'” – and whether to worry if your pre-schooler flunks the test.