Privileges in litigation are important tools they generally mean information can be withheld from the other side and the court because the privilege exists.
In matrimonial litigation (I love big words) a frequently invoked privilege is really a disqualification which means that private conversations between spouses can stay private. Other frequently used privileges are the patient-psychotherapist privilege and the lawyer-client privilege, both of which are designed to keep confidential communications confidential.
Another frequently used privilege, but not one that is often talked about, is the "Common Interest Privilege," about which my talented colleague Andrea Dunbar has written a post.
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