In Wisconsin the term "legal custody" refers not to where the children are to live but to the allocation of decision-making authority among the parties with respect to major decisions. The term "physical placement" is used to refer to where the children are to live, and the term "periods of physical placement" refers to the time the children are placed with a particular parent or custodian.

Legal custody may be sole or joint, or mixed sole and joint (joint in some areas but sole in others). Joint legal custody means both parents have a right to participate in major decisions affecting the children; sole legal custody means only the parent with legal custody has the right to decide major decisions affecting the children. Occasionally the court will grant joint legal custody on most issues but identify certain areas where one parent has sole legal custody.

The court may grant joint legal custody if it finds that it is in the best interests of the children and either both parents request it or one parent requests it and the court finds all three of the following: 1) both parents are capable of performing parental duties, 2) no conditions exist which would substantially interfere with the exercise of joint legal custody, and 3) the parties will be able to cooperate in the future decision-making required by joint legal custody.

Under certain circumstances the court may transfer legal custody to a relative of the children or to an agency if the court finds that neither parent is able to adequately care for the children. This third-party custody decision under a divorce decree is rare but seems to be becoming more common as more and more children are left with relatives by distressed spouses prior to divorce.

The court will want the children to spend time with both parents, and by statutory law must allocate periods of physical placement between the parties unless the court finds that physical placement with a parent would endanger the children's physical, mental or emotional health. Absolute denial of periods of physical placement is very rare, but if ordered, may provide a basis for eventual termination of parental rights.

In most cases each parent is awarded periods of physical placement of the children. The actual placement arrangement may take one of three basic forms:

If the parties cannot reach an agreement about the placement arrangement for the children the court may have to decide the issue after a trial. The interests of the children are represented at the trial by an attorney, known as a guardian ad litem, appointed by the court to represent the children's interests. A custody study is usually prepared for the benefit of the court and plays a significant role in the guardian ad litem's position and the court's decision.

The court shall consider the following ten factors in making its determination:

In the interest of introducing a period of stability for the children, Wisconsin has a two-year rule whereby during the first two years after a custody/placement order has been issued it is generally very difficult to revise the order to substantially alter the amount of time the children spend with the respective parents. The two-year rule is expressed as follows:

In order to make a substantial modification to a custody/placement order, the type of showing the moving party must make is different based upon whether the motion is made before or after two years have passed since the custody/placement order was issued:

However, there are three exceptions to the above two-year rule:

If a party moves to modify a custody/placement order and the other party opposes it, the parties are first referred to mediation to attempt to resolve the dispute. If the parties fail to mediate a solution, the court will likely appoint a guardian ad litem for the children and may even order a new custody study, based on the circumstances of the case and the nature of the motion.

The Wisconsin Statutes governing custody and placement are s. 767.24 (for initial orders) and s. 767.325 for revision of custody/placement orders.