Many times we see agreements or decrees that say the parents have joint legal custody and the mother (or the father) has physical custody of the children.
Legal custody is about long term parenting decisions, such as the education, health and religion of the children. Joint legal custody means the parents are to make those decisions together. Both have an equal vote and each has a veto power.
Physical custody means where the child resides most of the time. The other parent has visitation or access or timesharing. Each parent has care and custody of the child when they are with them, and can make day to day parenting decisions alone.
Here’s where legal world and real world part company. In the legal world, long term decisions are required to be made by agreement. But in the real world, if mom decides on her own to make Dr. A their pediatrician, dad usually doesn’t object. If dad does object, his only recourse is to take mom back to court and that usually costs more money than it is worth.
So sometimes, joint legal custody and primary physical custody ends up being, as a practical matter, the same as sole legal custody.