This pilot case study, as part of an international social work research project, explored how culturally relevant collaborative practices were perceived by international social workers. Semi-structured interviews were conducted with social workers (n = 4) who had worked as Japan Overseas Cooperation Volunteers for 2 years in another Asian country. Thematic analysis was applied to their narratives. Three main themes were found: 'socio-cultural understanding based on local life and activities', 'collaborative practice with local stakeholders' and 'attitudes and perspectives at the local practice'. Although the background and context of the interviewees' activities differed, they stressed the importance of deepening their socio-cultural understanding, together with learning local languages and deploying appropriate communication methods, through living in each locality and interacting with local people. They also described the process of exploring the collaborative activities through dialogue with local people, while taking a reflective view. These findings indicate the necessity for a deeper examination of collaborative practice by domestic and international social workers in various fields.