If you retain me to help you I, of course, want to solve both of your problems with the IRS so you can both rest easy.  Therefore, I will have to determine the best way to file your Offer.  Since you have been filing separate returns, the IRS will generally require a separate Offer from each of you.  I can do this in one of two ways, either two completely separate Offers with independent supporting financial documentation and sent at different times, or two Offers sent together with one set of supporting documentation.  One determining factor will be how you handle your day-to-day finances, e.g. joint bank accounts and whether or not bills are paid from joint funds.  The other big factor is how your assets are held, e.g., does one party have significantly more assets than the other.  After considering these and other factors, I will be able to decide the best way to submit the Offer to minimize your eventual combined payment.