Manipulation of the cervical spine (MCS) is used in the treatment of people with neck pain and muscle-tension headache. The purposes of this article are to review previously reported cases in which injuries were attributed to MCS, to identify cases of injury involving treatment by physical therapists, and to describe the risks and benefits of MCS. One hundred seventy-seven published cases of injury reported in 116 articles were reviewed. The cases were published between 1925 and 1997. The most frequently reported injuries involved arterial dissection or spasm, and lesions of the brain stem. Death occurred in 32 (18%) of the cases. Physical therapists were involved in less than 2% of the cases, and no deaths have been attributed to MCS provided by physical therapists. Although the risk of injury associated with MCS appears to be small, this type of therapy has the potential to expose patients to vertebral artery damage that can be avoided with the use of mobilization (nonthrust passive movements). The literature does not demonstrate that the benefits of MCS outweigh the risks. Several recommendations for future studies and for the practice of MCS are discussed.