Investigations in progress deal with the isolation and immunochemical properties of common allergens used in clinical allergy. Particular attention is being given to differences between the large and small molecular weight components found in preparations used clinically at present. Detailed studies on the water-soluble components of ragweed pollen antigens will hopefully be completed during the coming year and will provide the technical information for continuation of the general problem but dealing with different types of allergens, particularly the epidermals.