This article offers the reader a socio-cultural examination of a series of fundamental processes related to the construction and development of the professional teaching identity. By way of illustration, we analyse 39 subjective learning experiences reported by 12 novice teachers in Chile. The objective is to examine aspects of their experiences that facilitated or hindered changes in their identity positions. Our results suggest that the processes involved in the construction and development of identity are closely linked to their assessments of certain specific aspects of their experiences. These include (i) the material and social conditions found in highly demanding work environments; (ii) certain socio-cultural characteristics such as vulnerability in educational contexts; (iii) personal learning trajectories; (iv) interactions with students or your own experiences as students; and (v) a series of other characteristics that are not part of the situation as such, but that nevertheless influence it, such as educational policy.