In a commentary, Michael Kremer and Rachel Glennerster assert that the best way to fight infectious diseases like HIV, tuberculosis, and malaria is vaccines. The authors note that vaccines against these diseases "would be relatively easy to deliver and could be used by large numbers of people at low cost." The problem, however, is that drug firms are often reluctant to undertake research for diseases that affect mostly people in poor nations. A task force recently established by British Prime Minister Tony Blair suggested that industrialized countries fuel further vaccine research by agreeing to buy effective vaccines for HIV, TB, and malaria, upon development. Kremer and Glennerster call for immediate action on this front, noting that "if a commitment to purchase new vaccines fails to induce their development, it will have cost nothing; if it succeeds, it will save millions of lives at a few dollars each."