Bookkeepers track all cash flows, billing, and lines of credit that affect their companies. They must be detail-oriented and tenacious; they have to track down and rectify any discrepancies, however small, in the company accounts. Most bookkeepers work as internal accountants for small firms that do not have an accountant on staff. They have a large amount of responsibility to the company, and sometimes (particularly at the end of the year and around tax-preparation time) have to work long hours in order to do their job properly. The majority of bookkeepers work for smaller firms. Many become involved in financial tangles mid-stream-they find themselves deciphering records from up to a year before they were hired. Bookkeepers must be flexible and able to adjust to unusual circumstances