Drug overdoses are a major cause of mortality for drug users and, in many countries, are the leading cause of death in this group. The aim of the present study was to explore the frequency of all drug related deaths in the Split-Dalmatia County (Croatia) in period 1986 to 2000, and in the war (1991-1995), pre-war (1986-1990), and post-war period (1996-2000), and to analyze some characteristic of these deaths to help target preventive policies. An additional objective of this study was to investigate the quality of the data sources. The research find out that already proved risk factors causing overdose deaths are amplified by unfavourable wartime and post wartime events. Inaccuracies of used data sources require measures to improve their quality. The book is suitable for medical professionals, but it is the author hope that it should also provide useful information’s for those who have interests in this field, as well as health politics creators.