An S corporation that engaged a professional employer organization (PEO) to handle payroll and HR matters was liable for unpaid employment taxes and unfiled tax returns, actions that the PEO didn’t do, says the IRS. Solution: consider working with a certified PEO (CPEO), which is a bonded company that has met IRS guidelines. To date, the IRS has approved 84 CPEOs; expect more in the coming months.