[en] The Radiological Research Accelerator Facility (RARAF) is based on a 4-MV Van de Graaff accelerator, which can be used to generate a variety of well-characterized radiation beams for research in radiobiology and radiological physics. It is part of the Radiological Research Laboratory (RRL), and its operation is supported as a National Facility by the US Department of Energy. RARAF is available to all potential users on an equal basis, with priorities based on the recommendations of a Scientific Advisory Committee. Facilities and services are provided to users, but the research projects themselves must be supported separately. This chapter presents a brief description of current experiments being carried out at RARAF and of the operation of the Facility from January through June, 1986. Operation of the Facility for all of 1985 was described in the 1985 Progress Report for RARAF. The experiments described here were supported by various Grants and Contracts from NIH and DOE and by the Statens Stralskyddsinstitut of Sweden