In early childhood education, teacher professional development is crucial due to the impact of teachers on children's learning. This study presents the experience of action-research included in a teacher professional development program focused on improving pedagogical interaction from a sociocultural perspective. From 2012 to 2015, three cohorts of early childhood teachers from nursery schools located in vulnerable contexts participated in this program. These teachers developed intervention plans according to the action-research framework. In this report, these plans are analysed through a qualitative content analysis. Reports made by the participants and interviews with three tutors are also analysed. The results of the intervention plans show that most of them are focused on teacher professional development using video supported reflection to enhance the quality of interaction with children. In the reports, teachers identified important improvements in their skills, knowledge, beliefs and practices, and developed critical reflection on the process. Tutors found some problems during the program, which took them into a reflection process that led to transformations in their practice. These results are discussed in the context of a neoliberal society that might interfere with the development of alternative programs.