Chronic painful snapping scapula is characterized by inflammation and scarring of 1 or more bursae in the infraserratus space and is often refractory to conservative treatment. Surgical treatment involves excision of the bursae, as well as partial scapulectomy of the superomedial impinging region; both open and endoscopic approaches have been described with good results. Scapulothoracic endoscopy is technically difficult, and the potential complications can be serious. This report describes an endoscopic approach that can be performed with only 2 medial parascapular portals for visualization and instrumentation. The endoscopic anatomy of the infraserratus space is revisited, and 3 anatomic landmarks (serratus anterior, subspinous bursal curtain, and superomedial bony angle) are identified for safe dissection and intraoperative orientation. The surgical field is subdivided into 3 anatomic zones (superomedial space, subspinous space, and scapular bony angle), and the anatomic boundaries of these zones are demonstrated. The decompression procedure is subdivided into 4 stages (superomedial bursectomy, subspinous adhesiolysis, tuberoplasty, and scapuloplasty), and a measured resection technique for scapuloplasty is performed. The use of newer motorized rasps permits optimal bony resection, and additional portals are unnecessary. Overall, the step-by-step technique provides a methodical approach for safety, reproducibility, and optimization of the procedure.T he painful snapping scapula is a chronic disabling disorder of the scapulothoracic articulation and is characterized by painful crepitus and scapular dyskinesia. Structural and postural abnormalities predispose to development of adhesions and bursitis in the subspinous and superomedial infraserratus regions of the scapula. Structural bony abnormalities described in the literature include the Luschka tubercle and aberrant muscle attachments; in addition, an association between bony scapular morphology and snapping scapula has been suggested. 1-3 Failure of conservative treatment and the presence of an identifiable structural causative lesion are indications for surgical decompression. 4 Endoscopic-assisted and all-endoscopic scapulothoracic bursectomy with or without partial scapular resection has been described and is successful in approximately two-thirds of patients. [5][6][7] However, scapulothoracic endoscopy is technically difficult, and this is attributable to lack of a potentially distensible space, as well as the paucity of intraoperative anatomic landmarks for endoscopic orientation. Moreover, the proximity to the chest wall, apical pleura, and several neurovascular structures makes endoscopic exploration challenging. 8,9 The purpose of this report is to describe a step-by-step technique for safe scapulothoracic endoscopy using standard anatomic landmarks to guide dissection. The technique involves 2 portals for access to 2 scapulothoracic spaces (superomedial and subspinous), and the decompression procedure is subdivided into 4 stages (superom...