The United Nations Environment Programme highlights how the use of disposable nappies has become unsustainable, yet the practice of using modern cloth nappies (MCN) is niche. This study uses mixed methods of survey, story completion and focus group methods to explore how behaviour beliefs and attitudes to behaviour contribute to families’ decision making regarding the nappy system they use for their children. 1588 responded to the survey; 38 completed story completion activity; 24 participated in groups. This study finds that beliefs about the performance as a nappy, environmental credentials, financial considerations, laundry, effort, and hygiene differ according to the level of personal experience of using MCN. While beliefs about the environmentalcredentials of MCN create powerful drivers for the intention to use MCN, other beliefs about the upfront costs, laundry and effort contribute a negative attitude to MCN overall if their support network of other MCN users is not established. Current MCN users found using cloth nappy retailer websites, nappy libraries, and social media groups, including pre-loved and-sell groups, to be beneficial in improving attitude to MCN. This study concludes that interventions that simultaneously reduce or remove perceived barriers such as upfront costs, financial risks and too much effort, paired with campaigns which increase the likelihood of finding support, are more likely, than individual interventions, to be effective in increasing the number of families using MCN.Further study is needed to investigate the potential of interventions which reduce the financial risks such as, easy to access hire kits, spread the cost of MCN and pre-natal and newborn public services such as midwives and health visitors being well informed and encouraging of the use of MCN.<br/
