Objective. To evaluate the validity of the Activities-specific Balance Confidence scale (ABC) in people with multiple sclerosis (PwMS). Design. A multicentre, cross-sectional study. Setting. Six rural and urban Swedish sites, including specialized units at hospitals and primary care centers. Participants. A sample of 84 PwMS with subjective gait and balance impairment but still able to walk 100 m (comparable with EDSS 1-6). Outcome Measures. Timed Up and Go, Timed Up and Go(cog), 25-foot Timed Walk Test, Four Square Step Test, Dynamic Gait Index, Chair Stand Test, 12-item MS Walking Scale, self-reported falls, and use of assistive walking device were used for validation. Results. The concurrent convergent validity was moderate to good (0.50 to -0.75) with the highest correlation found for the 12-item MS Walking Scale. The ABC discriminated between multiple fallers and nonfallers but not between men and women. Ecological validity is suggested since ABC discriminated between users of assistive walking device and nonusers. The internal consistency was high at α = 0.95, and interitem correlations were between 0.30 and 0.83. Conclusion. This study supports the validity of the ABC for persons with mild-to-moderate MS. The participants lacked balance confidence in many everyday activities, likely restricting their participation in society.