Acupuncture is an ancient therapy characterized by a rapidly expanding scientific basis, increasingly integrated into U.S. healthcare systems despite persistent barriers in reimbursement and professional recognition. This segment details the robust research evidence concerning acupuncture’s mechanisms of action, particularly in pain management. At the local level, needle insertion generates immediate tissue effects by engaging connective tissue mechanotransduction; fibroblasts respond to mechanical signaling, altering inflammation and blood flow. Centrally, acupuncture is widely recognized for its influence on endogenous opioids (ß-endorphins, enkephalins), which correlates directly with rapid and sustained analgesia. Functional neuroimaging studies confirm that authentic needling not only activates the somatosensory cortex but also consistently deactivates affective and limbic brain regions like the amygdala, making it effective for addressing pain comorbid with anxiety and depression. Furthermore, auricular acupuncture engages vagal pathways to regulate autonomic function, beneficial for cardiovascular and gastrointestinal issues. Clinically, large meta-analyses provide robust support for acupuncture in chronic musculoskeletal pain, headache, and osteoarthritis, showing that it is not merely a short-term intervention but a durable therapy that can reduce long-term healthcare utilization. Acupuncturists must utilize this scientific language to educate patients and colleagues, strengthening their practices and advocating for greater integration into mainstream healthcare.