T HE RAPID movement or concentration of relatively large numbers of persons into and within the United States has presented certain difficulties in the control of venereal disease. Examples of such movement and concentration of population can be seen among workers in industrial defense plants, migrant farm and marine laborers, immigrants, potential civil defense mass evacuation groups, and similar population concentrations. Analysis of the problem as it relates to syphilis has suggested that effective control might be realized by use of a serologic test which would permit rapid and economical screening supplemented by immediate on-the-spot specific and prophylactic treatment of reactors at the times and locations where they are assembled for processing and assignment. To meet the requirements of a rapid serologic test for syphilis, a substitute for the conventional serum specimen was needed since considerable time and labor are involved in the processing of blood to serum. A review of the literature on the use of plasma in serologic tests for syphilis suggested that this type of sample might serve as the needed substitute for serum. Burdon (1, 2) noted that citrated plasma gave sensitive results in the Kline and Kahn tests than did serum. The greater sensitivity of plasma was attributed to the presence of more syphilitic in plasma than in serum. Fresh unheated plasma gave insensitive findings, but exposure at 56' C. water bath for 10 minutes was sufficient to raise the reactivity level to that obtained by heating for 30 minutes. It was necessary to centrifuge the plasma after heating to remove the precipitate which formed during the heating process. Burdon noted that considerable time was saved by the substitution of plasma for the conventional serum specimen. Barnard and Rein (3) found certain objections, such as increased anticomplementary findings and turbidity of specimen, to the use of citrated plasma and utilized the procedure of recalcification with dicalcium phosphate to obtain a serum specimen from the parent citrated plasma. Listed as advantages of this type of specimen were greater resistance to hemolysis of the citrated specimen, ease of separation of the plasma without resort to centrifugation, and greater stability of reagin in stored citrated plasma. The results on the recalcified plasma specimen had the same validity as those obtained with serum. However, the process of recalcification was rather laborious anid time-consuming. Barnard and Van Hala (4) substituted g ypsum for dicalcium phosphate for recalcifying citrated plasma. The inactivation of the specimen was accomplished in the presence of the clot and an excess of gypsum. In reports The authors are with the Public Health Service. Dr. Portnoy is an immunoserologist, and Dr. Garson is director, Venereal Disease Experimental Laboratory, Chapel Hill, N. C. Dr. Smith, deputy chief, Communicable Disease Center, Atlanta, Ga., was formerly chief, Venereal Disease Program, Division of Special Health Services, Washington, D. C. Technical assistance in the preparation of this paper was furnished by Jerry L. Smith, medical biologist, Venereal Disease Experimental Laboratory. The paper was presented in part at the Eighth Annual Symposium on Recent Advances in the Study of Venereal Disease, Washington, D.C., April 24-25, 1957.