This paper discusses the extent to which the professional development (cascade model) met its goal of improving mathematics teaching and learning during the implementation of National Curriculum Statement in South Africa. Fifty mathematics teachers from ten public secondary schools in Vhembe District in Limpopo Province of South Africa were chosen purposively. Using a qualitative approach, data were collected through a focus group discussion with five mathematics teachers at each of the ten schools. Teachers disapproved the manner in which the workshops were conducted claiming that they were disconnected from classroom practices. The conclusion was that: (a) the success of in-service programs should be determined by the way that the ideas, knowledge and skills learnt are implemented in a classroom setting; (b) for any in-service program that introduces teachers to a different instructional approach from the traditional one, it has to impact on teachers’ concerns (be they self-oriented, task-oriented or impact-oriented).