[en] This annual report presents information on the main activities carried out by the Nuclear Regulatory Authority (ARN) of Argentina during 1999, on radiation protection and nuclear safety. The work is developed in 9 chapters, 1 summary and 2 appendixes, where a description of the following activities and the bases of the Argentina Regulatory Systems are given: 1. Evolution of the nuclear regulatory activities in Argentina. Organic structures, tasks and budget. 2. Regulatory system, laws, transport of radioactive materials, safety at the management of radioactive wastes, regulatory documents issued. 3. Institutional relations with national and international organizations. 4. Inspection and evaluations of nuclear installations. Safeguards and physical protection. 5. Occupational and environmental surveillance. 6. Radiological emergencies. 7. Scientific and technological activities. Nuclear Regulatory Authority's laboratories. 8. Training, technical information and software development. 9. Radioactive facilities inspections