Purpose -This study explores how system trust affects customer relationships management in the Nigerian retail-banking context, a country with weak institutions and infrastructure. Design/methodology/approach -this is an exploratory study based on qualitative research using semi-structured interviews with 27 managers, and a review of documents on the Nigerian retail banking system. Findings -The major findings of the study is that weak system trust -due to the weak legal framework, low literacy level and ineffective policing, has an influence on technologydominated relationship marketing and reinforces interpersonal trust in the Nigerian retail banking context. Practical implication-the findings are significant to research and practice concerning how system trust affects the relationship management strategy of retail banks in the Sub-Saharan African market, and how banks mitigate the effect of system trust through staffs' interpersonal trust-building effort. Originality/value -This study is among the very few studies that link CRM implementation and system trust in the retail banking context that operate in the Sub-Saharan African market.