Risk management is an essential part of project management. There is an opinion that project management consists of risk management in most part: identification, potential risk treatments and assessment. Is risk management science or art? Is it expensive to manage risks in a project? How much do consequences cost? Is it always possible to control risks? How and why? This presentation is not intended to present international standards or special publications. The main aim is to provide simple principles, life examples, mistakes and loses as well as possible and actual consequences of untimely decisions and underestimated risks.