You have filed your returns but didn't have the money to pay what was owed. You may think, "Oh well---I will catch up next year." Before you know it you find yourself several years in arrears and suddenly there is a notice from the IRS, stating that you owe three or four times the original amount due to penalties and interest.
Allow an experienced CPA to help you work with the IRS to develop a payment plan or payment option that works for both parties.
