A golden age for ad technology has not translated into a golden age for advertising. Short-termism is rising, and effectiveness is falling. Recent work from the IPA has suggested that campaign effectiveness is deteriorating: it's increasingly rare that brands are achieving very large business effects. The same work tells us that the proportion of campaigns with short-term aims is on the rise, even though it's still long-term campaigns that create the greater uplifts in effectiveness. And finally, the number of channels continues to proliferate, with serious disagreements over which to focus on and how to make advertising work across them. It's never been more important or urgent that we ask ourselves 'what should a successful multi-platform campaign look like?'

The answer is to be found in behavioural science – the study of how human beings make decisions. The key insight from psychology and behavioural economics over the past 20 years is a growing realisation that we think much less than we think we think. Our decisions are guided primarily by what Nobel laureate Daniel Kahneman calls System 1 – a fast, intuitive, emotionally driven and automatic mode of thinking. On rare occasions we use our slower, more calculating System 2 thinking to change the decisions System 1 makes, but mostly System 2 is a'lazy policeman' that justifies and rubber stamps our gut feelings. The implication for marketers is simple: put most of your effort into designing for System 1.