In this chapter, we show how to interpret the financial statements of firms in the oil and gas industry. We first provide a tour of fundamental building blocks of financial statements noting items that are peculiar to the oil and gas industry. We present analysis of typical oil and gas firm financial statements considering profitability, efficiency, liquidity, and leverage. We use ratios and present two approaches to analysis – trend analysis and common size analysis. We end the chapter with a note on non-financial information and how that complements the analysis of financial data. Financial ratios are only useful for financial information analysis, but other non-financial information should be considered when conducting analysis of performance to get a full picture.