Economic analysis is aimed at the search for reserves to increase the effectiveness of a business company’s economic activity. The most important task is diagnostics and determination of the character of the effect produced by different factors on business processes. Financial and economic crises, that from time to time occur, belong to the most significant external factors that can have a strong effect on the stability of business structures. The author analyzes financial crises that took place in the last decade and also attempts to adapt the system of complex economic analysis to the conditions of crises.