Founded in 1993, the Yellowstone to Yukon (Y2Y) vision was one of the earliest large-landscape conservation visions. Despite growing recognition of large-landscape conservation strategies, there have been few tests to date of conservation gains achieved through such approaches. In this paper, counterfactual comparison provides valuable evidence that large-landscape conservation strategies such as Y2Y can enhance protected area growth and other conservation metrics. It concludes that large-landscape conservation strategies may be a useful model for achieving global large-landscape conservation and biodiversity conservation targets.