As teacher educators, preparing student-teachers who are able to address diverse student needs is our main concern. It has been suggested in the literature that teachers who are adaptive to students' needs are those who possess adequate pedagogical content knowledge or pedagogical understanding. However, it is not uncommon for teacher educators to find student-teachers with diverse pedagogical understandings even at the point of graduation from the teacher education programme. This paper aims to explain and analyse the development of pedagogical understanding among student-teachers in an initial teacher education programme. The findings are drawn from a study conducted at the Hong Kong Institute of Education where in-depth interviews were carried out during the four-year programme. The findings from the three selected cases provide an explanation for why some individual student-teachers show continuous development, whereas others remain confused in their pedagogical understanding throughout the teacher education programme. While acknowledging individual differences in pedagogical understanding, we attempt to explain such differences by investigating the relationship between different dimensions of the student-teachers' learning such as the integration of pedagogical understanding with the teaching contexts, integration of feedback from lecturers and supporting teachers, and their focus of concern. The findings reveal that the three cases demonstrate different levels of pedagogical understanding and possess varying 'senses of agency'. Of the three cases, the first one, Peggy has the strongest sense of agency. Despite influences related to classroom management, diverse learning ability among pupils, and the teaching methods which pupils were accustomed to previously, she actively introduced rhythmic movements into her lessons, developed pupils' ability to learn gradually and achieved an impact on pupils' learning which was also recognized by her supporting teacher. The