This paper examines the complex interweaving of the 'personal' and 'professional' in the affective labour of teachers. In line with theorisations of affective labour, contemporary school-teaching involves practices of self-work and self-making, as much as practices of curriculum and pedagogy. One emergent form of self-work, reflective of post-secular socio-cultural movements in education, is the use of contemplative practices (mindfulness, meditation, etc.) by teachers. Although mainly positioned within educational scholarship as techniques of stress-reduction, here we analyse contemplative practices as forms of affective labour. Drawing from a qualitative, empirical study, we explore how contemplative practices are embraced by teachers as ways to improve and transform the self -- both in relation to the professional responsibilities of teaching, and in relation to broader projects of living. The case studies presented demonstrate the deep political ambivalences of contemplative practices, as they are expressed in teachers' work. Contemplative practices do become incorporated into obligations towards self-improvement and increased productivity (what McGee labels 'the belaboured self'). However, they may also instantiate relational forms of ethical responsibility that move against the grain of instrumentalising, competitive, and individualistic education policy discourses and institutional life-worlds.