BACKGROUND: Much communicable disease control research has had little impact on local control programme policy and practice for want of an operational component. The operational research model - the systematic search for knowledge on interventions, tools or strategies that enhance programme effectiveness - is gaining recognition as an appropriate method for addressing perplexing questions within public health programmes. METHODS: A series of operational research studies were conducted to refine malaria diagnosis in Mpumalanga Province, South Africa between 1995 and 1999. The grounded theory approach was used with groups of experienced Masters of Public Health students in South Africa and Australia to analyse a compilation of these studies for determining positive and negative attributes of operational research that affect its ability to influence communicable disease control policy and practice. RESULTS: The principal positive attributes of the operational research studies were high local relevance, greater ability to convince local decision-makers, relatively short lag-time before implementation of findings, and the cost-effective nature of this form of research. Potential negative features elicited included opportunities forfeited by using scarce resources to conduct research and the need to adequately train local health staff in research methodology to ensure valid results and accurate interpretation of findings. CONCLUSIONS: Operational research effectively influenced disease control policy and practice in rural South Africa, by providing relevant answers to local questions and engaging policy-makers. This resulted in accelerated inclusion of appropriate measures into a local communicable disease control programme.