The reasons for the existence of this new Journal can be summed up in two statements: specialization is necessary for progress, and self expression is necessary for specialists. Specialization in tropical diseases has had a notable place in the medical work of our country and has been responsible for progress along many lines, not the least part of which has been due to the personnel of the Government Services. The story, however, is a continued one. Many diseases in the southern and border states still require the attention of the specialist in tropical diseases. In addition, the interests of the United States in its foreign possessions and in this continent and hemisphere have become more significant since the great war. Many of the problems to be faced have tropical medical aspects. Progress in handling these problems can come only by a continuation of the special work of the past.