Remote Tai Chi for Knee Osteoarthritis

Inclusion Criteria: * Age 50 years or older * Treating clinician diagnosis of knee osteoarthritis * Have a score of 40 (visual analog version) or greater on at least 1 of the 5 questions in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale (range of 0 to 100, with higher scores indicating greater pain) at baseline. * Able to provide informed consent * If randomized to the Routine Care group, willing to abstain from Tai Chi programs until completion of the study * If randomized to the Tai Chi group, willing to comply with the Tai Chi program (twice-a-week remote sessions for 12 weeks) * Has access to a home computer or device that will allow telehealth (bidirectional audio and video) delivery of the intervention * Is an active patient at one of the 4 participating healthcare system Exclusion Criteria: * Currently practicing Tai Chi * Serious medical conditions (e.g., dementia, significant neurological deficits or neurodegenerative disorder, active cancer treatment, psychosis, sensory deficits) limiting the participant's ability to participate in the Tai Chi safely, as determined by the principal investigators * Unable to walk without a cane or other assistive device * Any previous or scheduled knee replacement * Reports severe depression defined by a Beck Depression Inventory (BDI-II) score of 29 or more. * Reports suicidal ideations defined by a score on BDI-II item of 2 or 3 ('I would like to kill myself' or 'I would kill myself if I had the chance'). * Not English speaking * Enrollment in any other clinical trial within the last 30 days