Science Across the World is an exchange programme between schools world-wide. It has two main components: existing resources for students (age 6-10) and a database with all participating schools. The programme exists since 1990. It is carried out in partnership with the British Association of Science Education (ASE) and international pharmaceutical industry GlaxoSmithKline and is growing rapidly. This paper deals with the Science Across the World programme in Teacher Training in three countries: the Netherlands, Ireland and Germany. It shows how international collaboration can be fostered by participation in the programme. Amsterdam Teacher Training College in the Netherlands offers Science Across the World as an elective course to Dutch and European Erasmus students, who work in international interdisciplinary groups. They study the Science Across the World website and choose a topic to study in more detail. Later they write an implementation plan for their teaching practice school. At University College Cork in Ireland Science Across the World is part of a (Higher Diploma in Education) course on Science teaching methodology. Participating students implement the programme in their teaching practice schools. An elaborate research was carried out to investigate the success of this implementation. Teachers are enthusiastic about possibilities the programme offers and suggest an in-service training course on the programme and methodology. The government of the State of Hessen, Germany has just started a new concept in Biology methodology. The government decided to base Teacher Training in Biology on "Competencies and Standards." With increasing globalisation in the next decades the largest, easy to use, global exchange programme Science Across the World can help to achieve aims if modern education in all countries. Teacher Training can help with training student teachers in international collaboration on school level. The triangle Teacher Training--Science Across the World--Research should be promoted.