Chemical, Biological, Radiological, Nuclear, and high-yield Explosive (CBRNE) events have the potential to destabilize governments, create conditions that exacerbate violence or promote terrorism. This can trigger global repercussions. These events can quickly overwhelm the infrastructure and capability of the responders, especially in countries that do not have the specialized resources for response like those available in the United States. When a CBRNE incident occurs in a partner nation or other foreign country, the U.S. is often called upon to provide assistance. Interoperability - the ability to work together - among U.S. agencies, foreign governments, and responders involved in the effort is key to an efficient response. The effectiveness of the U.S. response and approach to CBRNE events in partner nations depends on the capability of the U.S. government to provide timely and appropriate assistance and the resilience of the partner nation to a CBRNE event. An All-of-Government Approach to Increase Resilience for International Chemical, Biological, Radiological, Nuclear, and Explosive (CBRNE) Events is the summary of a workshop convened in June 2013 by the National Institute of Standards and Technology and the National Research Council to discuss ways to strengthen the U.S. ability to prepare for and respond to CBRNE events that occur in U.S. partner nations. The workshop brought together diverse experts and stakeholders to identify capabilities that are necessary for responding to an international CBRNE event; discuss best practices and resources needed for improved interoperability of the U.S. and partner nation during response to a CBRNE event; and identify key questions that need to be addressed in follow up activities focused on improving U.S. CBRNE response in partner nations.