Our objective in the first study was to create a robust individual differences measure of fear of missing out. More specifically, we wanted to create a brief, self-report assessment that minimized participant burden and provided maximal information about an individual’s level of FoMO. To achieve this goal we paired theory guided method with latent trait theory analysis to craft a robust assessment of fear of missing out. To take full advantage of this approach we needed to start with a large pool of potential FoMO items. Based on are view of popular and industry writing on FoMO (e.g.,JWT, 2011; Morford, 2010; Wortham, 2011) we drafted 32 items mean to reflect the fears, worries, and anxieties people may have in relation to being in (or out of) touch with the events, experiences, and conversations happening across their extended social circles. We framed participants’ reading of and responses to scale items in terms of what really reflected their general experiences instead of what they thought their experiences should be. 1842A.K.Przybylski et al./Computers in Human Behavior 29(2013)1841–1848