Apparatus and method for surgery is disclosed which includes a retractor having a substantially planar base defining an opening for overlying an operative site on a patient, and at least one retractor blade slidably mounted to the base. The base is positioned on the patient such that the opening therein overlies the operative site. The operative site is percutaneously accessed, and obstructing tissue is retracted by engaging the tissue with the retractor blade. A surgical instrument is provided which is engageable with the base and operable at the operative site through the opening in the base. A surgical procedure is carried out through the opening in the base with the surgical instrument.