Firms have three general types of fund sources available to them: internally generated cash and short-term or long-term funds from external sources. External funds can come from lenders or investors. Lenders typically loan money in the form of commercial bank loans for short to medium term durations, or private bonds for the long term. Investors provide money to the company by buying the securities that it issues in the financial markets. These (generally) tradable securities can be either equity or debt, debt being the preferred choice.

Mark-to-market accounting is all about the accounting standards of assigning a value to a position held in a financial instrument based on the current fair market price for the instrument or similar instruments. It was originally practiced in the early 1990s. Under mark-to-market accounting, the use of fair value measurements has increased steadily over the past decade, primarily in response to investor demand for relevant and timely financial statements that will aid in making better informed decisions.