Recent scholarship in professional development (PD) has advocated for solid conceptual frameworks and understanding of the complex process involved in how language educators may continue to develop and fulfil the current challenging teaching demands. However, specific relationships underlying departmental cultures and how language educators relate to professional development activities are not completely understood, particularly in large programmes implementing curricular reforms. This paper reports on the outcomes of a PD programme framed within three main notions of sociocultural theory (learning by doing, scaffolding and collaboration) and designed to support a language programme reform in higher education in the United States. Drawing from observation and PD programme data, findings indicate that beyond the expertise and open spaces to participate, language educators need to be engaged in content meaningful to them and manageable within the context of their second language teaching practices. The embeddedness of individual acts of both teaching and reflection about it becomes the bedrock for significant PD and is fundamental to transform language teaching practices.