The book is dedicated to the definition of fair value. This type of valuation is especially important when combining, merging and acquiring companies, when it is important to know the real value of assets, including intangible assets, real estate and liabilities. The book is not a practical guide for appraisers, but is focused primarily on customers and consumers of information on evaluation - financial managers, accountants, analysts and auditors. The author answers a number of important questions, without which almost no assessment is possible. how to choose an appraiser and what expectations from the activities of the appraiser are adequate? How is fair value determined and on what assumptions it is based? How to determine the quality of the assessment report? How are financial instruments evaluated? How to assess corporate liabilities, such as lawsuits and conditional payments?