This publication is the new edition of the International Basic Safety Standards. Since publication of the previous edition in 1996, the contents have been extensively revised and updated. The publication details the requirements for the protection of people and the environment from harmful effects of ionizing radiation and for the safety of radiation sources. All circumstances of radiation exposure are considered. The printed book is available in English only. The companion CD-ROM includes translations of the text into Arabic, Chinese, French, Russian and Spanish. The text of this Interim Edition has been submitted to potential sponsoring organizations for their approval. Following their decisions on its approval, it will be issued as a jointly sponsored standard. This Interim Edition is reproduced directly from IAEA Board of Governors document GOV/2011/42 and has not been edited or typeset by the IAEA.