When Daniel X. Freedman invited me to serve as Guest Editor of this special issue on lithium, my response was immediate and affirmative. In the first place, I, like most of my colleagues, find it nearly impossible to say no to Dan Freedman. In addition, the obvious importance and timeliness of an Archives issue on lithium rendered Dan's invitation an honor and a challenge that I was very pleased to accept.
The approval of lithium carbonate for use in the United States did not occur until more than 20 years after Cade's original report of its efficacy in the treatment of "psychotic [manic] excitement." In spite of this striking lag in the awareness and acceptance of the drug in this country, in the recent past we have witnessed a profound and increasing impact of lithium, not only on the practice of American psychiatry, not only on the practice of American psychiatry, but also on large areas of