CONTEXT: Arthralgia is common and debilitating for a significant proportion of breast cancer survivors (BCSs) and leads to poor adherence to aromatase inhibitors (AIs). Despite increased recognition of the negative impact of arthralgia on function and the poor adherence that results, very few interventions have been developed to target this side effect. OBJECTIVE: This study aimed to determine the feasibility of tai chi to improve well-being for women experiencing AI-associated arthralgias (AIAAs). DESIGN: The study was a pilot to (1) demonstrate the feasibility of recruitment and retention for a tai chi trial, (2) determine the safety of tai chi, and (3) identify the outcomes (function, pain, and quality of life[QOL]) that tai chi may impact. SETTING: The study took place at the Gilda's Club South Jersey in Linwood, NJ, USA. PARTICIPANTS: Postmenopausal women with a history of stage I-III breast cancer reporting AIAA were enrolled. INTERVENTION: Group tai chi was practiced for 1 h 2 ×/wk for 8 wks. OUTCOME MEASURES: Functional outcomes included (1) sit-and-reach (SR), (2) functional reach (FR), (3) the Berg Balance Scale (BBS), and (4) timed up-and-go (TUG). The following patient-reported outcomes (PROs) were evaluated pre- and postintervention: (1) the Hospital Anxiety and Depression Scale (HADS), (2) the Functional Assessment of Cancer Therapy-Breast (FACT-B), (3) the Functional Assessment of Chronic Illness Therapy Fatigue (FACIT-Fatigue), (4) the Brief Pain Inventory (BPI), (5) the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity (FACT-GOG-Ntx), and (6) the Functional Assessment of Chronic Illness Therapy- Spiritual Well-being Scale (FACIT-Sp). Participants also recorded their tai chi experiences in a journal. RESULTS: For the 12 participants, adherence to the classes was 75%, with no adverse events reported. Participants experienced significant improvement from baseline to follow-up for the HADS anxiety (P = .003) and depression (P = .020) scales, the emotional well-being scale of the FACT-B (P = .027), the FACIT-Fatigue (P = .030), and the sit-and-teach test (P = .016). The BBS (P = .090), TUG (P = .241), BPI severity subscale (P = .058), and physical well-being subscale of the FACT-B (P = .052) showed no significant improvement. Participants reported increased relaxation, reduced stress, and enhanced sleep quality and duration. They valued the group's and the instructor's support. CONCLUSION: The research team demonstrated the feasibility of a tai chi intervention for improving wellbeing for breast cancer patients with AIAA and identified measures that may be sensitive to the impact of a tai chi intervention in this population.