This report was prepared to inform planning in the USAID-funded ASPIRES project. It includes a review of some of the existing tools used to assess vulnerability to either separation or negative child well-being outcomes with attention to economic security for the purposes of targeting households for program participation and matching them to appropriate interventions. ASPIRES is sharing this report as an information resource with the wider interested community given its relevance to other actors working in this area. The report begins with an overview of the concept of vulnerability, describing how it is used in the contexts of both child protection and economic strengthening programming. It goes on to propose a set of criteria for selecting and developing vulnerability measures for project targeting, drawing on existing standards of assessment in the fields of both child protection and economic strengthening. The report then discusses the vulnerability assessment approaches used by several organizations and programs working on issues related to child separation, followed by an analysis of the vulnerability assessment methods used according to the proposed evaluation criteria. It concludes with a discussion on the patterns identified in the analysis, as well as recommendations for future assessments and suggestions for future research on vulnerability assessment.