Objectives. To evaluate the impact of implementing an evidence-based fall prevention intervention in community senior centers. Methods. We used a single-group design to evaluate the Tai Ji Quan: Moving for Better Balance (TJQMBB) program's adoption, population reach, implementation, effectiveness, and maintenance among 36 senior centers in 4 Oregon counties between 2012 and 2016. The primary outcome measure, as part of the effectiveness evaluation, was number of falls as ascertained by self-report. Trained TJQMBB instructors delivered the program to community-dwelling older adults for 48 weeks, with a 6-month postintervention follow-up. Results. TJQMBB was adopted by 89% of the senior centers approached and reached 90% of the target population. The program resulted in a 49% reduction in the total number of falls and improved physical performance. Participation was well maintained after the program's completion. The average cost-effectiveness ratio for the 48-week program implementation was $917 per fall prevented and $676 per fall prevented for multiple falls. Conclusions. TJQMBB is an effective public health program that can be broadly implemented in community senior centers for primary prevention of falls among community-dwelling older adults. [ABSTRACT FROM AUTHOR] Copyright of American Journal of Public Health is the property of American Public Health Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)