Strengthening national health laboratory systems in resource-poor countries is critical to meeting the United Nations Millennium Development Goals. Despite strong commitment from the international community to fight major infectious diseases, weak laboratory infrastructure remains a huge rate-limiting step. Some major challenges facing laboratory systems in resource-poor settings include dilapidated infrastructure; lack of human capacity, laboratory policies, and strategic plans; and limited synergies between clinical and research laboratories. Together, these factors compromise the quality of test results and impact patient management. With increased funding, the target of laboratory strengthening efforts in resource-poor countries should be the integrating of laboratory services across major diseases to leverage resources with respect to physical infrastructure; types of assays; supply chain management of reagents and equipment; and maintenance of equipment.