GlaxoSmithKline's (GSK) hygiene initiative is PHASE, Personal Hygiene and Sanitation Education, a simple and successful handwashing programme developed alongside children and their teachers for implementation in and through schools. Active since 1998, it is currently implemented in 15 international development settings. An evaluation of PHASE reported that the programme had proved to be highly effective and amenable to cross-cultural adaptation. PHASE is currently being transferred to UK primary schools with development taking place in London. During this process issues of ‘South to North’ knowledge transfer (experience, relevance and acceptance) have become key to the design and execution of the programme. This article reports work in progress.