While public health laws have been in existence for many centuries, the legislative history of protection against ionizing radiation is recent. The U. S. Advisory Committee on X-ray and Radium Protection in 1929 initiated recommended standards for radiation protection. The standards developed, expanded, and revised subsequently, served as the basis for Federal legislation in conjunction with the atomic energy program of the 1940's. State legislatures and public health authorities also, responding to the same needs felt on the federal level, have greatly increased the radiation protection role of State and local governments within the past decade. Amendments to the U. S. Atomic Energy Act in 1959, permitting States to assume certain regulatory functions administered by the Atomic Energy Commission, have further stimulated State programs. This report is a summary of developments over the past decade in State legislation and regulations affecting radiation protection or control. It also includes tabulations by States of enacted, proposed but not passed, and not completed legislation (this last a valuable indicator of current trends) for the calendar year 1965.