There is accumulating evidence suggesting that hepatic permeability to both naive and activated T lymphocytes may be unique among the solid organs. The possibility that the liver may act as a site of primary activation for CD8⁺ T lymphocytes is supported by experimental data and may contribute to some of the unique immunological properties of this organ, particularly its ability to induce antigen‐specific tolerance. This review discusses the nature of the liver APC inducing primary T‐cell activation within the liver: Kupffer cells, liver dendritic cells, liver sinusoidal endothelial cells and hepatocytes are favourably located to allow physical contact with circulating T lymphocytes. Here, we examine the capability of each cell type to act as APC for naive CD4⁺ or CD8⁺ T cells and to induce tolerance.