OBJECTIVE:: Sarcomas are rare mesenchymal malignancies. Accurate preoperative diagnosis is a prerequisite in considering investigational or institutional management algorithms that include neoadjuvant treatment. We reviewed our experience using core needle biopsy for chest wall sarcomas. Methods: A retrospective review of our sarcoma databases revealed that 40 core needle biopsies and 35 tumor resections were performed in 34 patients, with chest wall musculoskeletal tumors, referred to the University of California, Los Angeles from 1991 to 2010. Primary, metastatic, or recurrent sarcomas involving the sternum, ribs, and soft tissues of the chest wall were evaluated for (1) adequacy of tissue from image-guided core needle biopsies and (2) accuracy in determining malignancy, histological subtype, and sarcoma grade. Results: Twenty-eight of the 40 needle biopsy samples (70%) were adequate for histopathological analysis. Forty-two percent of nondiagnostic findings occurred due to insufficient tissue, whereas the remainder had sufficient tissue, but the pathologist was unable to determine specific histology. Excluding the nondiagnostic samples, the accuracy in determining malignancy, histological subtype, and grade in sarcomas was 100, 92, and 87%, respectively. The sensitivity and specificity of determining malignancy and high-grade sarcomas were 100, 100, 77, and 100%, respectively. There were no complications from the image-guided biopsies. Conclusions: We demonstrated that image-guided core needle biopsy when performed and reviewed by experienced radiologists and musculoskeletal pathologists is a safe and accurate diagnostic technique for chest wall sarcomas. Core needle biopsy should be considered in the multidisciplinary approach to chest wall musculoskeletal tumors, especially when induction therapy is considered. Copyright © 2011 by the International Association for the Study of Lung Cancer.