The ethical provision of psychological aid following international disasters is influenced by cultural factors and questions about how to effectively promote social justice. A need for holistic, systemic postdisaster mental health approaches has been identified (Wessells, 2009). This article presents a systemic epistemology superimposed on a social justice framework as a model for conceptualizing ethical service delivery in international disaster psychology. Implications of three underlying conceptual perspectives in international mental health ethics—absolutism, relativism, and universalism—are discussed. A case example is provided that illustrates how a family systems epistemology offers a flexible, integrated way to understand the universalist approach while placing social justice concerns relevant to international disaster psychology into a nested model, where the whole is greater than the sum of its parts.