This rather lengthy monograph deals with an extremely careful, thorough and intelligent investigation of the incidence of endemic goiter among the rural population of Denmark. As studies elsewhere have also shown, areas with a high incidence of goiter were found to have little iodine in the drinking water. The finding of similarly low iodine content in the drinking water of districts without particularly high incidence of goiter suggests the existence of other factors in the production of goiter than lack of iodine alone. The monograph is in Danish, but there is an excellent English summary by Dr. Hans Andersen.