Bad pregnancy outcome includes abortion, stillbirth, neonatal death, morbidity, malformation, cerebral palsy, and mental retardation. These afflictions cause devastating personal impact. In the United States, almost 10% of all school-aged children are handicapped. Neurologic and communicative disorders affect 42 million people and cost $114 billion each year. The cause of cerebral palsy is known in less than 10% of these cases. Enormous litigations have threatened clinicians, paramedical personnel, hospitals, and insurance carriers. The placenta is an important potential means of establishing that fetal damage causes bad pregnancy outcome independently of clinical care. All pathologists serve an important role in the documentation of gross placental features and in the procurement of appropriate light microscopic slides. Pathologic placentas are common. Only an expert can determine whether an abnormal placenta represents the probable cause of bad pregnancy outcome.