The chain of progression from teacher education to qualification to classroom instruction and student engagement, and then to learning and achievement, is not as straightforward as often presented. Societal, political and economic pressures create either a positive climate or a stressful one for both teachers and students. Nevertheless it is safe to say that in a subject like mathematics, the importance of subject matter knowledge cannot be underestimated. Research in this area supports the presumption that formal qualifications in the subject, in this case mathematics, are necessary, as this focused engagement with mathematics provides the foundation for mathematics teaching and learning. The allocation of fully qualified teachers to schools has in the past been uneven, with the supposition that students at higher socio-economic levels are being taught by better qualified teachers. In South Africa the improvement of teacher qualifications has been identified as a core area of action with the relevant policy on teacher education renewed in 2007 and again in 2014. The focus of this paper is to understand the change in patterns of teacher qualifications, and the interrelationship with school contextual variables. The analysis is based on the Trends in International Mathematics and Science Study (TIMSS) data from 2003, 2011 and 2015, where teachers from the TIMSS sample provided contextual information. Descriptive statistics were calculated using the IEA IDB Analyzer. The results show that South Africa has made substantial progress in uplifting teachers' formal qualification levels and in reducing structural inequality within its education system. Out-of-field teaching of mathematics is still shown to be a common phenomenon and is unevenly distributed.