Acute coronary syndrome without ST segment elevation (NSTE ACS) is cardiovascular illness with increasing incidence in developed countries and is connected with high morbidity and mortality rates. European society of cardiology presents recently new Guidelines for the diagnosis and treatment of NSTE ACS. This material gives complex overview of the management of this serious and potentially life threatening state. Therapeutic approach (pharmacology treatment or coronary angiography and revascularization) is based on early risk stratification. Risk assessment in NSTE ASC needs to address the risk of both thrombotic and bleeding complications.