Under the direction of the US Global AIDS Coordinator's Office, Department of Health and Human Services, the CDC Global AIDS programme helps resource-constrained countries to address the global HIV/AIDS pandemic. Activities include laboratory capacity and laboratory infrastructure development in 25 resource-constrained countries. Medical practitioners and public health programme leaders in industrialized countries rely on the use of quality laboratory data for evidence-based medical decision-making to determine policy for the implementation of disease control measures, to monitor disease to determine the impact of control programmes, and to support surveillance activities. In these countries, laboratory data to support decision-making processes have a level of quality attributable to laws, regulations and guidelines developed over many years. However, resource-constrained countries have not had similar experiences. Few countries have developed laws, regulations or guidelines, nor is there a data-use culture (e.g. evidence-based medicine) for those in the decision-making environment in resource-constrained countries. The strengthening of laboratory capability and capacity in resource-constrained countries is an important goal to improve accurate and reliable data for the diagnosis, treatment and monitoring of disease.A process for the implementation of a quality systems approach for a laboratory is presented: (i) acknowledgement of the need to improve the laboratory programme in the country at the Ministry of Health and at all decision-making levels within the provinces/states of the country; (ii) assessment of capabilities, capacities, infrastructure, and training needs; (iii) implementation of a national meeting of laboratorians; (iv) designation of a national Quality Assurance Office and leadership within that office; (v) the development and provision of technical training.