Nudging is a controversial technique for changing people's behaviours. It burst into public consciousness in the early 2000s with the launch of "nudge units" and departments in government.

The use of nudges as a policy tool is particularly polarising, as their implementation raises moral and constitutional issues about freedom, choice and coercion. Whitehead and Jones take a balanced approach to explain where the nudge as a mechanism for policy implementation came from (as far back as the 1930s), what a nudge is, whether we should use them and, if so, when and where are they best deployed. The proliferation of digital media through our lives has given nudging a new impetus and sphere of operation, which the authors explore to understand its likely future use by policymakers.