FANTA held a technical consultation on February 12–13, 2018, in Washington, DC, to explore whether standardized mid-upper arm circumference (MUAC) cutoffs can be used to identify acute undernutrition among adults. The gathering of stakeholders and anthropometry experts reviewed and discussed the results of FANTA’s individual participant-level data meta-analysis that explored the diagnostic accuracy of various MUAC cutoffs for identifying undernutrition among adults, compared to BMI. By the end of the meeting, the group agreed that MUAC is an indicator for undernutrition in adults, determined the data gaps for further study, and established the next steps in moving toward recommending a single or set of global MUAC cutoffs.