Antibodies are critical for immune protection against a wide range of pathogens and for the functioning of most if not all vaccines. Gabriel Victora’s work focuses on various aspects of how antibody responses are constructed with special emphasis on the germinal center reaction, where a Darwinian process known as affinity maturation drives an increase in B cell and antibody affinity over time. His work combines microscopy with mouse genetics to investigate how the clonal and cellular dynamics of B cells within and outside germinal centers shape the potency and specificity of the antibody response.