permission of the examinees, copies of all examination and laboratory data from the Brookhaven program are forwarded to the Marshall Islands Health Service hospitals on Ebeye and Majuro and to the 177 Health Care Program, a special program set up for persons from the radiation-affected atolls, with administrative offices at the Majuro hospital. In addition, copies of the examinations and laboratory data are given to the examinees themselves. The Marshall Islands Medical Program, as a satellite clinic of the Clinical Research Center, Brookhaven National Laboratory, is accredited by the Joint Commission on Accreditation of Healthcare Organizations, a nationwide organization that sets standards of performance for institutions dispensing medical care and monitors compliance with those standards. By voluntarily participating in the accreditation process, the Brookhaven National Laboratory Marshall Islands Medical Program receives a valuable and impartial external review of its policies and procedures, as well as an assessment of the adequacy of the services it provides. Laboratory and radiological services, medical records, patient satisfaction, pharmaceutical services, and clinical competence of physicians are among the many items reviewed by the Joint Commission. Procedures: The exposed population, which in December 1991 numbered 159, must be considered at increased risk for malignant disease as a late complication of radiation exposure. Therefore, the medical program has in place a canceroriented annual health evaluation. The examination follows the guidelines of the American Cancer Society and includes a medical history, complete physical examination, advice on decreasing the risk factors for cancer, advice on self-detection of lesions, annual pelvic examinations and Papanicolaou smears, blood count, urinalysis, stool testing for occult blood, annual mammography (offered to all exposed women andto all unexposed womenforty years of age or older), and flexible sigmoidoscopy (every three years for personsfifty years of age or older). Every two years ophthalmologists are included on the medical team andslit-lamp examinations are provided. A wide selection of reading glasses and glasses for aphakic individuals are included on each mission. These glasses, of great practical value to the island populations, have for years been kindly provided free of charge by New Eyes for the Needy (P.O. Box 332, Short Hills, NJ). It is known, because of earlier medical program observations, that the exposed are at increased risk for certain endocrine problems. Therefore,. they receive annual thyroid function blood tests and thyroid examinationsby a specialist in endocrinology or thyroid surgery. Needle biopsies of thyroid nodules were performed onselected patients in an effort to avoid surgery and the subsequent loss of normal thyroid tissue. Other serologic tests are performed ona regular basis in an attempt at early detection of malignant nonthyroidal lesions. These include serum protein electrophoresis, calcium, prolactin, alpha-fetoprotein levels on persons known to have hepatitis B surface antigenemia, and thyroglobulin determinations on those whose thyroid surgery specimens suggested a malignant lesion. There is also ongoing monitoring for clinical evidence of immune competence, for exposed persons may be at increased risk for infectious disease or unusual manifestations thereof. Specialized tests on the comparison population were referred as clinically indicated. Medical examinations and services performed during this four-year reporting period were conducted primarily aboard the Liktanur ITI, owned by U.S. Oceanography, San Diego, CA, and the G. W. Pierce, a vessel owned by Tracor Marine, Ft. Lauderdale, FL. These ships were chartered by the U.S. Department of Energy for the purpose of supporting several of the Department of Energysponsored Marshall Islands programs, of which the medical program is but one. Somepatients were examinedin the island dispensaries on Mejatto and Utirik, and home visits were arranged for the elderly who preferred not to be moved aboard the ship. Clinical laboratory services for the missions were performed by several Brookhaven National Laboratory technicians with support from personnel of the Health Services of the Republic of the Marshall Islands. Routine hematology testing was performed on a J.T. Baker 5000 electronic counter and, beginning in the fall of 1989, on the Serono Baker 9000 RX automatic 8-parametercell counter. Leukocytedifferentials and platelet counts were part of each evaluation. Clinical chemistry tests were