Luminex technology allows the accurate identification of human leukocyte antigen (HLA) class I and class II-specific antibodies at levels below the threshold detectable by either conventional complement-dependent lymphocytotoxicity or flow cytometry. The technology enables the analysis of complex antibody profiles in sensitized patients and gives improved definition of acceptable and unacceptable HLA specificities to guide donor kidney allocation. This helps to facilitate virtual cross-matching and avoid inappropriate shipping of kidneys for incompatible patients in distant centers. Luminex allows the cause of a positive cross-match test to be determined in a clinically relevant time scale and, when used in conjunction with lymphocytotoxic and flow cytometric cross-matching, it provides an assessment of the level of immunological risk in patients being considered as potential recipients for a particular donor kidney. Information is now emerging to enable the full clinical potential of Luminex to be realized.