BACKGROUND AND PURPOSE: Tibialis posterior tendinopathy can lead to debilitating dysfunction. This study examined the effectiveness of orthoses and resistance exercise in the early management of tibialis posterior tendinopathy. SUBJECTS: Thirty-six adults with stage I or II tibialis posterior tendinopathy participated in this study. METHODS: Participants were randomly assigned to 1 of 3 groups to complete a 12-week program of: (1) orthoses wear and stretching (O group); (2) orthoses wear, stretching, and concentric progressive resistive exercise (OC group); or (3) orthoses wear, stretching, and eccentric progressive resistive exercise (OE group). Pre-intervention and post-intervention data (Foot Functional Index, distance traveled in the 5-Minute Walk Test, and pain immediately after the 5-Minute Walk Test) were collected. RESULTS: Foot Functional Index scores (total, pain, and disability) decreased in all groups after the intervention. The OE group demonstrated the most improvement in each subcategory, and the O group demonstrated the least improvement. Pain immediately after the 5-Minute Walk Test was significantly reduced across all groups after the intervention. DISCUSSION AND CONCLUSION: People with early stages of tibialis posterior tendinopathy benefited from a program of orthoses wear and stretching. Eccentric and concentric progressive resistive exercises further reduced pain and improved perceptions of function.