A system for accessing a spine from a curved postero-lateral approach may include a curved cannula positioned along a curved path from an opening in the skin to a location proximate the spine. A targeting post may be inserted adjacent the spine to determine the location. A peritoneal retractor and a guide member may be first inserted to establish the path between the tissues and fascia, and one or more intermediate cannulas may be temporarily inserted over the guide member to dilate the tissues prior to insertion of the main cannula. An interbody device may be implanted in an intervertebral space through the cannula. An endoscope may be inserted through the targeting post or the cannula. The system may include instruments with shafts which are flexible or are curved to match the curve of the curved cannula, including a rongeur, curette, rasp, distractor, trial implant, probe, tamp, and implant inserter.