[en] In the presented ''Annual Report 1999'' the scientific, organizational and educational activities of the Andrzej Soltan Institute for Nuclear Studies (SINS) are presented. The document is divided into two parts. First of them consists of the general information about management, scientific council, departments of SINS, scientific staff, visiting scientists, list of research project (grants) as well as information about PhD and DSc theses. The second one: ''Reports on Research'' describes the research activities of SINS. It is divided into 12 sections - in which the works of SINS departments and establishments are presented (Department of Nuclear Reactions, Department of Nuclear Spectroscopy and Technique, Department of Nuclear Electronics, Department of Radiation Shielding and Dosimetry, Department of Plasma Physics and Technology, Department of High Energy Physics, Department of Cosmic Radiation Physics, Department of Nuclear Theory, Department of Radiation Detectors, Department of Accelerator Physics and Technology, Department of Training and Consulting and Establishment for Nuclear Equipment). Each of these sections is preceded by short overview given by the head of given department. The foreword, in which the whole activities of the SINS are summarized, given by head of the Institute professor Z. Sujkowski is also given