The Radiation Epidemiology Branch (REB), of the Division of Cancer Epidemiology and Genetics (DCEG), of the National Cancer Institute (NCI) intends to negotiate with the Radiation Effects Research Foundation (RERF), Hiroshima, Japan for a five year support services contract entitled, "Support For Epidemiological Studies of Cancer Among Atomic Bomb Survivors". This is a renewal of Contract No. N01-CP-31012 with the National Academy of Sciences, who has been subcontracting out the majority of the work for this on-going project to the RERF since 1979. This is a transition to a new phse of of this on-going project.  The RERF owns and has been maintaining the Life Span Study (LSS) a continuing long-term cohort study of 94,000 atomic bomb survivors and 26,000 non-exposed residents in Hiroshima and Nagasaki. This cohort is among the largest populations exposed to external low linear energy transfer radiation. The cohort follow-up based on nationwide mortality tracing (since 1950) and active cancer incidence surveillance (since 1958) consists of both males and females of all ages, including a large number of persons exposed at infancy and during childhood. In addition, a unique cohort of 3,600 subjects who were exposed to radiation in utero is the only human population in which long-term cancer risk data are being accumulated. Well-characterized individual radiation dose estimates, most recently updated in 2002, are available for 95% of the cohort. The most important finding from the long-term follow-up of the LSS cohort is the persistently increased risk of solid cancer attributable to radiation, which is demonstrable 60 years after the atomic bombs and which may last for life (Preston, Shimizu et al. 2003; Preston, Ron et al. 2007). Up to the present time, over 17,500 incident cases have occurred in this cohort, and 850 of these were estimated to be excess cases due to radiation exposure - a far greater number observed than in the other large cohorts. This renewal will be negotiated directly with RERF as a support services contract with the emphasis on supporting various epidemiological and multi-disciplinary studies of cancer that will be characterizing organ- and tissue specific cancer risks, modifying and interactive effects on the radiation-related cancer risk, and undertaking molecular genetic studies in the LSS. Authority: 41 USC 253 (c) (1), as set forth in FAR 6.302-1. The proposed contract is for supplies or services for which the Government intends to solicit and negotiate with only one source under the authority of FAR 6.302. Interested persons may identify their interest and capability to respond to the requirement or submit proposals. This notice of intent is not a request for competitive proposals. However, all proposals received within 45 days after date of publication of this synopsis with be considered by the Government. A determination by the Government not to compete this proposed contract based on responses to this notice is solely within the discretion of the Government. Information received will normally be considered solely for the purpose of determining whether to conduct a competitive procurement. No collect calls will be accepted.