The challenge of motivating 25.4 million households to complete and return a 56-question, 32-page census questionnaire is a sizeable task. For 200 years government enumerators personally hand delivered and collected questionnaires, but declining response in 2001 called the model into question. In the 2011 Census, for the first time, marketing communications took the lead in delivering the majority of responses allowing enumerators to focus efforts in a more efficient way against non-responders. The campaign met the challenge, saving £20m and ensuring statistical accuracy, inclusivity and value-for-money, informing £100bn public expenditure. The ROMI is calculated as £2.93 for every £1 spent