Evaluating network infrastructures for potential vulnerabilities is an important component of strategic planning, particularly in the context of managing and mitigating service disruptions. Many methods have been proposed to facilitate such analysis, providing different interpretations of infrastructure vulnerability. The primary approaches that have been employed for network vulnerability analysis can be broadly classified as "scenario-specific", "strategy-specific", "simulation", and "mathematical modeling" methodologies. Research on network vulnerability assessment has traditionally focused on one of these methodologies without consideration of the others. This article highlights the important implications of methodology for both infrastructure planning and policy development. To better understand the theoretical and practical trade-offs associated with methodology selection, this article provides a review of these categories of analysis, examining benefits and shortcomings with regard to practical planning issues and policy interpretation. Copyright (c) 2008 Copyright the Authors. Journal compilation (c) 2008 Wiley Periodicals, Inc..