BACKGROUND: Community health workers (CHWs) provide maternal and child health services to communities in many low and middle-income countries, including South Africa (SA). CHWs can improve access to important health interventions for isolated and vulnerable communities. In this study we explored the performance of CHWs providing maternal and child health services at household level and the quality of the CHW-mother interaction. METHODS: A qualitative study design was employed using observations and in-depth interviews to explore the content of household interactions, and experiences and perceptions of mothers and CHWs. Fifteen CHWs and 30 mothers/pregnant women were purposively selected in three rural districts of KwaZulu-Natal, SA. CHW household visits to mothers were observed and field notes taken, followed by in-depth interviews with mothers and CHWs. Observations and interviews were audio-recorded. We performed thematic analysis on transcribed discussions, and content analysis on observational data. RESULTS: CHWs provided appropriate and correct health information but there were important gaps in the content provided. Mothers expressed satisfaction with CHW visits and appreciation that CHWs understood their life experiences and therefore provided advice and support that was relevant and accessible. CHWs expressed concern that they did not have the knowledge required to undertake all activities in the household, and requested training and support from supervisors during household visits. CONCLUSIONS: Key building blocks for a successful CHW programme are in place to provide services for mothers and children in households but further training and supervision is required if the gaps in CHW knowledge and skills are to be filled.