Biomagnetic liver susceptometry is a non-invasive measurement of liver (and spleen) iron stores. Proposed by Bauman in 1967, it was demonstrated on animals@footnote 1@ shortly thereafter. With the development of the Superconducting quantum interference device (SQUID) magnetic field sensor, a prototype system was developed for measurement of human liver iron stores. Measurements on normal and iron overloaded subjects showed this technique to be an accurate quantitative measurement of human iron stores@footnote 2@. The basic system is comprised of a superconducting magnet, a highly sensitive SQUID magnetic field sensor, a water bag (placed between the sensor and patient) that simulates the natural magnetism of the body, a non-magnetic bed and data acquisition system. Since the installation of the first clinical systems at Cleveland and Hamburg, over 6,000 clinical measurements have been made on over 4,000 patients. We describe the measurement technique and present summaries of a number of clinical studies comparing biomagnetic liver susceptometry to needle biopsies. We describe the current status of both the original systems@footnote 3@ and improved systems now being produced and comment on future directions in the non-invasive measurement of liver-iron stores including the possibility of assessment of cardiac iron. @FootnoteText@ @footnote 1@ Bauman JH, Harris JW, "Estimation of hepatic iron stores by in-vivo measurement of magnetic susceptibility", J Lab Clin Med 1967; 70: 246-257.@footnote 2@ Brittenham GM, Farrell DE, Harris JW, Feldman ES, Danish EH, Muir WA, Tripp JH, Bellon EM."Magnetic-susceptibility measurement of human iron stores", N Engl J Med 1982; 307: 1671-1675.@footnote 3@ Paulson DN, Fagaly RL, Toussaint RM, Fischer R, "Biomagnetic Susceptometer with SQUID Instrumentation", IEEE Transactions on Magnetics, vol 27, no. 2, March 1991.