The purpose of this paper is to report the early experience with Transesophageal Echocardiography (TEE) after its availability at Thoracic Surgery, Hospital S. João, Oporto, Clinical advantages of the esophageal acoustic window over other approaches and technical development background of the procedure are reviewed. Updated clinical indications of the procedure and illustrative clinical cases from daily practice are presented. From October 1990 to February 1991, 75 examinations have been performed, 59 in awake patients and 16 in unconscious patients, either in the operating theatre or in intensive care unit. The examination protocol was similar to the one followed at Mayo Clinic. All patients accepted to undergo the study when indicated. No technical difficulties were found and no complications were reported during the study period. Finally, based on this introductory experience, a comment is made on main indications for using TEE complemented by few notes on future perspectives with this using ultrasound technique.