With a view to promoting a shared understanding of the proper approach to Article 1(F)(a) exclusion from refugee status, we have engaged in sustained collaborative study and reflection on relevant norms and state practice. Our research was debated and refined at the Sixth Colloquium on Challenges in International Refugee Law, convened in March 2013 by the University of Michigan’s Program in Refugee and Asylum Law. These Guidelines are the product of that endeavor, and reflect the consensus of Colloquium participants on how decision makers can best ensure the application of Article 1(F)(a) in a manner that conforms to international legal principles.