Transference and countertransference feelings/reactions are a valuable source of information about a patient's inner world. A consultation liaison psychiatrist has to help the entire treatment team to understand the patient as well as treat the patient. Studies about transference and countertransference in medical settings are insufficient. An idealized transference often develops, usually at the beginning of the treatment, whereas negative transference occurs rarely. At other times a displaced transference, with anger directed toward the medical team or one of its members may develop. Acute intense transference and countertransference feelings/reactions may be indicators of serious character pathology, such as Cluster B personality disorders. Patients with terminal illness are in need of perceiving the physician as an ideal and omnipotent figure, therefore, encouragement of a regressive relationship is recommended. There is always a risk of either avoidance or over involvement with the patient, especially in cases of catastrophic illness or injury. Not infrequently, interaction with the patient may evoke a traumatic experience in the therapist that has not been worked through sufficiently, and may hinder the therapist's ability to relate to his patient. Therapist countertransference feelings may be informative about the entire medical treatment process of the patient. Collaborative meetings with the medical team may help a therapists to understand their patients' inner worlds and to correct his/her dysfunctional attitudes, which in turn might positively affect treatment compliance and improve prognosis. Herein, the literature regarding transference and. countertronsference in medical patients is reviewed with case examples.