CXCL13 was initially described as a chemokine, highly expressed in the follicles of Peyer's patches, spleen, and lymph nodes, and as a strong chomoattractant for B cells. CXCL13 is expressed by T follicular helper cells, dendritic cells, and stromal cells (including marginal reticular cells (MRCs) and follicular dendritic cells (FDCs)) in B cell areas of secondary lymphoid tissue. CXCL13 binds to CXCR5 that was initially cloned from Burkitt’s lymphoma cells and named BLR1. B cells migrate in lymphoid organs in search of specific antigens. B cells enter lymph nodes through high endothelial venules and migrate through the lymph node follicle in a CXCL13/CXCR5 dependent manner. During the B cell migration in the follicle, they are in contact with FDCs, MRCs, and cells localized around the follicle perimeter, such as sinus-associated macrophages and T cell zone-associated DCs. Subsequent to the migration through the FDC network, the B cells travel through the T cell zone-proximal follicle. In this migration, CCL21, CCL19, CCR7 and CXCR5 are involved. CXCL13, CCL19, and CCL21 take part in the formation of tertiary lymphoid tissues in chronic antigen-induced arthritis. High expression of CXCL13 has been linked to lupus, Helicobacter pylori-associated gastritis, multiple sclerosis, rheumatoid arthritis, and the allergic airway inflammatory process. In summary, CXCL13 is highly expressed at sites of new lymphoid tissue formation in a variety of chronic inflammatory conditions.