This thesis examines the extent to which teachers’ lives and practices are influenced and shaped by policy and reform. The data draw on life history interviews with eight primary school teachers who have extensive practical experience working as classroom teachers, principals, and advisors. Most of the participants work in schools serving areas of socio-economic disadvantage. The participants have taken part in a range of initiatives aimed to combat educational disadvantage and to improve children’s participation in schools. The findings of this research suggest that teachers who work in disadvantaged schools have more opportunities to vary their teaching roles and to experience change and reform than their colleagues working in middle-class settings. Change is a constant motif in many of the participants’ careers. They emerge as change agents, leading reforms as school principals or through their involvement in school-based change initiatives. All of the participants have experienced externally generated reforms, many of which provide opportunities for professional development and personal growth. Their engagement in locally-based professional networks maintains their enthusiasm and their receptivity to change. The research finds that policy texts have little significance for teachers’ lives and work. While most of the participants have attained Master’s or other post-graduate qualifications, their engagement with policy texts is extremely limited. Principal teachers and others working in advisory services were more aware of policy and its implications for their work than classroom teachers. The pace of educational reform in Ireland in the last decade has led to change overload. For many of the participants there is insufficient time, support or opportunity for them to implement the full extent of the reforms and to embed them in their practice. However, the participants continue to exercise their professional discretion concerning their level of involvement with different reforms and they interact with reforms that resonate with their personal values and missions. The participants make a significant emotional investment into their work and while entering the later stages of their career, they remain enthusiastic and committed and are open to change and innovation. The desire of this group of teachers to continuously broaden their horizons and to experience new challenges is unique. The study concludes that the participants’ career trajectories are individual and are formed by personal biography and by their previous experiences of change and role diversification in their schools. Their successful engagement with reforms is enhanced through their ongoing engagement in further studies and their participation in professional networks.