This special issue of the African Evaluation Journal, in memory of the late Dr Sulley Gariba was a collaborative project led by EvalPartners with the support from the United Nations World Food Programme, in partnership with regional Voluntary Organisations for Professional Evaluation (VOPEs) in the Global South, including the African Evaluation Association (AfrEA), the Latin American and Caribbean Network of Monitoring, Evaluation and Systematization (ReLAC) and the Asia Pacific Evaluation Association (APEA). It builds on three memorial lectures delivered at conferences organised by these regional VOPEs between 2022 and 2023. EvalPartners with support from WFP and UNICEF conceptualised the Sulley Gariba memorial lecture series shortly after his passing in April 2021 in honour of his contribution to the global evaluation community.