We evaluate the impact of collaborative management agreements (CMAs) designed to protect forests and raise incomes for smallholders living adjacent to Rwenzori Mountains National Park (RMNP), Uganda. We use a quasi-experimental study design to estimate changes in several income measures, as well as land cover using three waves (2003, 2007, and 2012) of household survey and remote sensing data. Overall, we find no significant impact of CMAs on any of our income measures. However, when disaggregating households by income quartile, we find that access to forest resources in RMNP may have had an income stabilizing effect for poor households. Forest income grew significantly faster among the poorest quartile of treatment relative to control households, partially because poor households recorded very low income from forests at baseline. The effect of CMAs on forest cover is minimal, although we find that conversion of woody savanna and savanna to cropland is more pronounced in villages with CMAs. These findings suggest that in the medium-term, CMAs have failed to deliver conservation or development benefits related to enhancing livelihoods or conserving forests near RMNP. Practitioners should consider different CMA models or other strategies for improving welfare and forest health outcomes in communities neighboring protected areas.