The July 1986 issue of the Archives together with the other AMA journals will begin the first phase of our two- year conversion to reporting laboratory values in Systéme International (SI) units.^1,2 The AMA House of Delegates guided by the AMA Council on Scientific Affairs mandated in December 1984, that several parts of the SI system be adopted. This system is currently used by the majority of the world, and its adoption has been fostered by the necessity for fluent international scientific communication and uniformity. Lehmann³ has previously reviewed the arguments regarding this shift.

Conventional units followed by SI units in parentheses will be used during the first year to allow acculturation of the majority of physicians who are unfamiliar with this system. Changes in laboratory values that will be most readily noticed include the use of the mole to express amount of substance, adoption of the millimole