These comments reflect an experience obtained from examining fetal pancreatic alpha- and betacell responsiveness in the nonhuman primate, Macaca mulata. Our research studies encompassed nine years in two different institutions with two different colonies of monkeys. A maternal glucose-intolerant state was obtained through the use of streptozotocin (SZ). We found that the induced glucose-intolerant pregnant female monkey lent itself to an exploration of the fetopathy that occurs in human pregnancy associated with diabetes mellitus.