Immunoperoxidase staining of samples of normal human retina and choroid was performed to demonstrate selected adhesion molecules in vivo. Intercellular adhesion molecule-1 (ICAM-1), lymphocyte function-associated antigen-3 (LFA-3) and endothelial leucocyte adhesion molecule-1 (ELAM-1) were expressed on retinal vascular endothelium and ICAM-1 and ELAM-1 in the region of the external limiting membrane. The very late antigen-2 (VLA-2) was found around the retinal ganglion cells and in the inner and outer fibre layers. The endothelium on the choriocapillaris showed moderate staining of ICAM-1, and slight staining of LFA-3 and ELAM-1. The presence of these molecules in this distribution strongly suggests they have an important role in the pathogenesis of immunologically mediated ocular conditions.