South Dakota permits legal separations. The plaintiff files a petition for separation and the spouses agree in writing to provisions for child and spousal support, and property division.

A separation agreement is a legal binding contract signed by spouses, which is intended to resolve property, debt and child related issues. This can be a very complex and detailed document depending upon the unique situation of the marriage. Many spouses consult an attorney to provide this or they decide to prepare their own.

The grounds for legal separation are the same as the grounds for divorce. South Dakota offers both fault and no-fault grounds. For no-fault grounds, “irreconcilable differences” is the standard. Fault-based grounds require considerably more specific reasons, including: adultery, extreme cruelty, willful desertion, willful neglect, felony conviction, and abuse of controlled substances or alcohol.

The filing spouse must reside in South Dakota or be a member of the armed forces stationed in South Dakota at the time of the action, and he or she must remain in South Dakota until the separation is final.

The plaintiff files a summons and complaint with the clerk of the Circuit Court in his or her county of residence. That spouse states that the couple has been living "separate and apart." The summons and the complaint are served on the defendant. The spouses can then create a separation agreement addressing property, maintenance and custody. If they can't do so, a court decides the outstanding issues using standards as if the spouses were divorcing.