Science teachers’ education has a fundamental influence on the quality of science education at all levels of instruction. This chapter focuses on the benefits of infusing a humanities perspective into the education of science teachers for sustainable development. Although Education for Sustainable Development (ESD) was initiated 30 years ago, there has been little evidence of reaction from the national science curricula of South Africa. It is suggested that science teacher education curricula should change appropriately in advance of school curricula changes which must be made eventually. This requires careful development of parts of the existing curricula for prospective science teachers to include content, skills and attitudes suited to ESD. This would lead to a more humanistic science teacher education.