Even though you and your spouse are ready to file for divorce and agree as to how you will settle all the issues in your marriage, you may still need to have a Separation Agreement.
This Agreement is a contract between you and your spouse that settles everything related to your property, your retirement accounts, your children, issues of support, etc.
Once the Agreement is signed, you can then file for an Uncontested Divorce as long as you have met the required separation period.
So, even though it seems that you can just go ahead and file for divorce, it is important to be sure that you have protected yourself with an Agreement that clearly spells out how you are settling your finances and other issues that have arisen as a result of your marriage.