Being audited by the IRS can be a very stressful event for individuals or business owners. People immediately think they either inadvertently did something wrong when they filed their tax return, or they believe the IRS found out about something they were trying to hide in their tax return.

But audits may occur for several reasons, sometimes even randomly. The IRS’ computer system may select a tax return for audit. Each return entered into the IRS computer system receives a numerical score. If your score is high, there’s a good chance you may be audited. For a business, the score depends on various factors, such as high auto expenses, low gross profit margin, little or no business profit, or high travel and entertainment deductions.

For individuals, as their income increases, so do their chances of being audited, although the average American’s chances of being audited are actually less than 1 percent. Some flags that may trigger IRS audits of an individual’s tax return include having a return with a large amount of itemized deductions, unreported taxable income, a record of tax deficiency, large charitable donations of cash, claims of tax shelter investment losses, reporting rental expenses, or having had a prior audit. Sometimes even taking all of your legitimate tax deductions may be cause for an audit.

There are four main types of IRS audits: (1) Correspondence Audit—the IRS will mail a letter to request copies of receipts for expenses you claimed; (2) Office Audit—you are responsible for bringing all requested documents to the IRS at an appointed time; (3) Field Audit—an IRS agent comes to your residence or business and either goes through your files with you or takes them to go through them himself; (4) TCMP Audit—a total audit where everything on your return must be validated.

It’s vital to be organized and have all appropriate paperwork and documents at hand and in order in the event of an audit. You are only responsible to supply the documents the IRS requests. Most tax attorneys advise to never offer additional information. Be sure to make copies of all your documents and receipts and keep the originals yourself. A tax attorney may act as a representative through the audit process. Once the auditor reaches a decision, you can either agree with it and pay the amount owed, or you can choose to disagree with the findings and therefore appeal the decision.