The assistive conservation approach includes strategies for conserving community-based lands based on a complex combination of traditional and modern scientific knowledge. It enjoys broad legitimacy and seems promising for conserving territories with autochthonous populations. However, as a novel strategy, it has been applied mostly to societies and environments that are fragile in conservationist terms. This paper critically analyses the evolution of environmental discourses on nature conservation, assesses their related strategies and methodologies, and shows how emerging discourses have been assimilated to produce a qualitative shift from ‘top-down’ to ‘bottom-up’ models of environmental management, but without eliminating considerable dependence. It reviews earlier critiques of the protected areas approach associated with this emerging concept. Finally, it revisits the evolution of an important early case of assistive conservation, La Ventanilla (Oaxaca, Mexico), to assess processes of dependence and this emergent strategy's potential to face challenges of environmental degradation. It concludes that, over time, this concept makes local ecologies more vulnerable to social and environmental degradation, especially as traditional management institutions once responsible for ecological integrity become obsolete.