Social and cultural differences between the United States and the United Kingdom mean that positive results from US prevention programmes may not translate to the United Kingdom. The Strengthening Families Programme 10-14 (SFP10-14) has been evaluated in a large Phase III randomized controlled trial in rural Iowa in the United States and shown to be effective for delaying alcohol and drug initiation. This paper reports the first stage of the adaptation and evaluation of the SFP10-14 for the United Kingdom through a process of cultural accommodation of the SFP10-14 materials and format. Themes that emerged in nominal group and focus group research with young people and their parents indicated that changes to the US SFP10-14 materials needed to consider language, narrators, realism, acceptability of exercises/games, perceived religiosity and ethnic representativeness. However, not all changes reflected straightforward cultural differences, as adaptations were also required to improve the quality and to update the material, indicating that cultural accommodation does not necessarily imply cultural diversity.