A financial expert that is schooled in tax law is called a tax advisor. In some countries it is mandatory by law to have a tax advisor verify the balance sheets of companies that grow beyond a certain size. Individual persons usually call on the services of a tax advisor because they don't understand tax law and do not want to take the time to learn it. A tax advisor can be a company's only means of making certain that they are in compliance with tax laws with regard to their company. This is because there is rarely any staff on the company's payroll that is educated enough in tax law to be able to make certain that all these laws are adhered to.