According to all three evaluation methods, US-based research in immunology plays a dominant role in the worldwide effort. Within the limitations of each measure and the limits of the panel's use of them, the data produce a strikingly consistent outcome: all three approaches assigned a 2:1 to 3:1 dominance vis-a-vis the rest of the world. Of course the dominance needs to be weighed in relation to the relative richness of the United States in numbers of investigators, institutions and resources.