Initial science teacher education in Hong Kong is provided by the Post-graduate Diploma in Education Programme (PGDE) for both pre-service and in-service secondary school teachers. This programme includes a balanced treatment of subject curriculum and teaching in science, general pedagogical knowledge and skills, educational psychology and school administration. The science courses in this programme also have some units that equip science teachers with the knowledge and skills that are essential for teaching a science curriculum that emphasises conceptual change and understanding of the nature and methods of science. This emphasis is illustrated by two studies: (1) Developing a conceptual change model of instruction in Biology teachers, and (2) Constructing understanding of the nature and methods of science.