In an industry commonly characterised as emotionally demanding, challenging and exhausting, it is not surprising that support workers’ are exposed to wellbeing and service quality threats at work. Despite the growing acknowledgement of these work characteristics, research into the psychosocial factors attributable to these outcomes has received modest attention. The purpose of the current study is to examine the role of supervisor feedback and support in sustaining wellbeing and ensuring service quality in the support work setting. Further, the research aims to uncover additional psychosocial factors that influence these outcomes, through qualitative analysis. 146 support workers from a large New Zealand care organisation participated in an online survey administered at two time points. As expected, supervisor feedback and support was a significant predictor of the wellbeing and service quality of support workers; however, this relationship was modest. In addition, analysis of the open-ended responses revealed the significant influence of other supervisor factors, as well as the job design and characteristics, and organisational systems. These findings indicate the scope of factors that influence support workers’ wellbeing and service quality, and highlight the need to take all levels of job, supervisor and organisation into account. Future research is needed to further investigate these factors and their relationship with these outcomes.