This volume of The Year in Immunology series features reviews of topics in human immunology, including B1 B cells, BCL-2 family members, Wiskott-Aldrich syndrome, reverse vaccinology, anti-b₂-glycoprotein I, the role of autoimmunity In thromboangiitis obliterans (Buerger's Disease), long pentraxin PTX3 as a paradigm for humoral pattern recognition molecules, and control of inflammatory heart disease by CD4⁺ T cells.