Transsphenoidal microsurgery is a well-established neurosurgical procedure that has become the standard of care in the management of the majority of pituitary tumors and a select group of other sellar lesions. The safety of the procedure depends on the surgeon's adherence to certain anatomic concepts. Foremost among these concepts is the necessity of preserving the integrity of the arachnoid membrane covering the tumor dome and avoiding vascular injuries in the cavernous sinus. The objective of this article is to demonstrate the sequential steps of a transsphenoidal microsurgical procedure for the removal of a pituitary tumor in light of the anatomic concepts discussed, with the goal of preventing complications and achieving the best possible outcome.