In many settings a perplexing scenario is unfolding in which school systems claim to move towards whole-person development while students and parents run in the opposite direction of narrowly defined academic achievement enhanced by private supplementary tutoring. Such tutoring is widely called shadow education because much of its content mimics that of regular schooling. It has long been clearly visible in Asia, and is now increasingly visible elsewhere. This study focuses on school teachers' perceptions of shadow education in the context of a flourishing sector that parallels and to some extent contradicts progressive education reforms. Drawing on 47 in-depth interviews with teachers from 12 secondary schools in Hong Kong, the research found ambivalent views towards private tutoring. This ambivalence reflected intrinsic contradictions between the educational ideals of whole-person development and the function of schooling in social stratification. Such tensions are likely to become increasingly evident elsewhere as commercialised forms of private supplementary tutoring expand.