Indigenous and Western communities are faced with increasing issues of sustainability compromising their natural resources and cultural heritage, for example, a cross-pollination/complementary approach in relation to their current knowledge systems and discourses on sustainability. There is a need for methods that integrate different discourses relating to sustainability to identify the most pressing needs in terms of sustainability. Sustainability assessments are a type of impact assessment that focus on enhanced sustainability both now and in the future; however, the literature on indigenous sustainability assessment methods, is scarce. To address this gap, we have developed a novel Sustainability Assessment method for Indigenous Communities (SAIC). The SAIC method combines Western and indigenous sustainability objectives and principles, in order to extend the range of options for action to address sustainability. The SAIC method consists of two sections (i) values and considerations and (ii) procedure. The "values and considerations" section establishes the fundamental participatory and ethical considerations for conducting sustainability assessments in indigenous communities, and the “procedure” section establishes a set of 55 indicators in eight categories. The method was tested in a Zapotec, indigenous community in México. Results show that this community was rated highly in all eight categories. However, indicators for family planning and access to health services were rated poorly. The identified issues can be used as guidelines for decision making in future regional projects and development plans. The results reveal further areas for improvement, such as strengthening the links to national or international networks and increasing the use of renewable energies. The method presented in this paper provides an assessment approach based on Western and indigenous sustainability discourses, which is suitable for assessing indigenous communities.