A retrospective, single-institution, single-surgeon, case series is presented of adrenalectomy in 70 canine patients at the University hospital for companion animals in Utrecht, the Netherlands. Patients received a standardized endocrinological work-up and contrast-enhanced CT imaging of the abdomen (and pituitary in case of hypercortisolism). The choice of surgical approach was based on CT findings and was either a flank laparoscopy in sternal recumbence, or paracostal laparotomy in lateral recumbence. Surgical technique (45 laparoscopic, 25 open; 8 bilateral, 62 unilateral), diagnosis, and short- and long-term outcome will be presented, and comparison of open versus laparoscopic cases is made.