Why is Mexico's third sector underdeveloped? Despite the importance of this question, there is no persuasive answer. The usual mono-causal explanations –such as historical trajectory or lack of civic culture– are inadequate. A better way to address this question is applying the concept of an enabling environment for civil society. This encompasses empowering legal and fiscal frameworks, an effective accountability system, adequate institutional capacity of organizations, and availability of resources. The article offers an assessment of where Mexico stands in relation to these five components and argues that on each count they are unfavorable and/or underdeveloped. In addition, the author argues for including a sixth element: the cultural context for philanthropy and civil society. Based on original survey results, he demonstrates that key values and habits inhibit efforts to strengthen civil society and must be taken into account in any effort to understand or change the status quo. The article concludes with a reflection on how Mexican civil society can begin to change its unfavorable context, beginning with the need for stronger mechanisms for greater accountability on the part of organizations.