Drawing on the findings of a three-year, longitudinal study investigating early career teachers' (ECTs) experiences and perceptions of leadership development in English secondary schools, this paper highlights, from the perspectives of ECTs, some of the factors that support and facilitate leadership development during the first few years of the teaching career. ECTs' leadership dispositions and aspirations seemed to be formed within and in response to what they perceived to be the nature of their particular school contexts. They appeared to position themselves in relation to the perceived school leadership ethos at a range of points along what might be conceptualised as a continuum from resistance and alienation to amenability and identification with the perceived ethos. Amenability and identification with the school leadership ethos seemed to be associated with high levels of personal agency, such that ECTs gathered important developmental experience as leaders and were developing leadership skills, dispositions and aspirations. In a minority of contexts, ECTs experienced feelings of alienation, and positioned themselves as resistant to school leadership in contexts they perceived to be characterised by high accountability, blame and coercion. This resistance and alienation were associated with reduced agency, and restricted development as leaders.