We tested psychometric properties of the Markers of Adulthood (MoA) importance scale and a revised Inventory of the Dimensions of Emerging Adulthood (IDEA-8) in a large, diverse multisite and multinational sample the Emerging Adulthood Measured at Multiple Institutions 2 project. We used multilevel confirmatory factor analyses and multilevel alphas to examine external validity and internal consistency of the scales. We also performed correlational and exploratory multilevel analyses to determine the extent to which emerging adulthood dimensions overlap across scales. The IDEA-8 subscales demonstrated acceptable psychometric properties. Our research suggests that recent approaches to combine the MoA markers provide four modestly reliable factors, but perceptions of adulthood varied considerably as a function of sample. We recommend that the structure of these marker items be examined for any given sample, since their relative importance seems to vary, not just across time but also sample location.