This book contains theory about psychological phenomenon - adolescence, risk and impulsivity. Presented research includes more than 2000 pupils at the age of 11 to 16 years. The schools of those pupils were randomly chosen from Zlinsky a Moravskoslezsky region. The results were compared with two nationwide researches. Chosen psychological phenomenon were examined with diagnostic tools Škála impulsivity Dolejš a Skopal (SIDS) and Výskyt rizikového chování u adolescent (VRCHA). These tools have high validity, reliability and mutual connection. We gained valid information from two regions, those results show current situation in that area. The results about impulsivity and risk behaviour bring many practical recommendations for school prevention officers, special pedagogues and other experts.