In an ageing and ever lonelier society, volunteering based on intergenerational relationships is becoming an increasingly salient form of support, but also a valuable leisure activity. With the help of thematic analysis, the study explored (1) how young adult volunteers working with seniors perceive their work and (2) what encouraged them to take up the volunteering role and what makes it easier or possible for them to remain active. Interviews were conducted in Poland in 2020 with 10 volunteers aged between 22 and 35 (6 women, 4 men) who had experience of working with seniors during the year preceding the study. Seven issues emerged from the analysis: the context in which volunteering began; personal characteristics of the volunteer; daily difficulties of the elderly; keeping the senior company in transience and loneliness; attachment and relationship between the volunteer and the elderly person(s); personal benefits of involvement in volunteering; social benefits of involvement in volunteering. The results were discussed in the light of the volunteer process model and the types of volunteers’ motivations. Several volunteers also pointed to the role of volunteering not only in building a norm of reciprocity in relationships with seniors, but also more broadly in the society.