If you have not yet gotten married, you can protect your retirement benefits using a prenuptial agreement. A prenuptial agreement is a legally binding contract that outlines how property division and other matters will be decided should the couple ever get divorced. You can include your pension plan and retirement benefits in your prenup, if desired, to protect them from being divided with your spouse in the event of a divorce. If you are already married, you may still be able to protect your pension plan with a postnuptial agreement.