It is estimated that the functionally significant body of knowledge for a given medical specialty changes radically every 8 years. New specialties and "sub-specialization" are occurring at approximately an equal rate. Historically, established journals have not been able either to absorb this increase in publishable material or to extend their readership to the new specialists. International and national meetings, symposia and seminars, workshops and newsletters, successfully bring to the attention of physi- cians within developing specialties what is occurring, but generally only in...