This article contains important messages for all those with an interest in enhancing the effectiveness of professional development supported by websites. It is informed by the findings of a Training and Development Agency for Schools (TDA) funded evaluation of the use and effectiveness of three websites whose development the TDA had supported. Data were collected from teacher educators and student teachers from a variety of initial teacher education (ITE) providers by means of face-to-face, telephone and e-interviews, as well as case study visits. It was found that although all three websites were regarded as being high quality, their effectiveness in supporting professional development varied. This article considers possible reasons for this and implications for other websites, not just within the English and schools contexts, but also more globally.