Critical infrastructure asset identification is a core component of the risk management process. Amidst growing concerns of terrorist and natural disaster threats to the critical infrastructure, it is imperative that public and private sector stakeholders understand exactly which assets are critical to national security in order to prioritize risk management efforts. Challenges to accomplishing this task are the difficulty in identifying exactly which assets are critical and comparing the risks to assets across the many critical infrastructure sectors. A proven method for critical infrastructure asset identification that meets these needs does not exist today. This chapter explores the critical infrastructure protection policy frameworks and requirements of the United States, European Union and other countries, and summarizes the key requirements and methodologies. The methodologies are analyzed against the outlined requirements. Based on this analysis, a new approach is presented for critical infrastructure asset identification and additional research using multi-criteria decision theory is proposed to resolve the challenges that have limited progress in this area.