The psychotherapist-patient privilege, rooted in both common and statutory law, is predicated upon the public policy goal of protecting the reasonable expectation of privacy of individuals seeking psychotherapy. The privilege is not absolute, however. State and federal courts are far from uniform in determining how and when the privilege should be waived, in whole or in part, through implication, inadvertence or the affirmative action of the parties. In the family law context, the law that has evolved around the exercise of this privilege is even more complex as the needs of children add another wrinkle to the goal of balancing the imperative of confidentiality with the need for useful information that may be provided.