Measures of complexity have been repeatedly criticized for their lack of theoretical foundation and construct validity (e.g. Biber et al., 2011; Norris and Ortega, 2009; Pallotti, 2015). Prominent scholars in the field have also advocated for an expanded view of complexity, emphasizing its multifaceted and multidimensional nature that cannot be fully explored through a singular dimension. Instead, it necessitates operationalization through a battery of measures tapping into its different facets (e.g. Bulté and Housen, 2012; Ortega, 2012). Within this framework, Paquot (2019) argued that a successful renewal of the domain would also require a better appreciation of the phraseological dimension of language use in L2 complexity research. There remain, however, a number of unresolved issues with the way phraseological complexity has been operationalized since Paquot (2019). In this talk, I will argue more specifically that there is a need to revisit the dimension of phraseological sophistication and how it has been used to describe L2 proficiency/development. I will share findings from a study that re-analyses the VESPA learner corpus used in Paquot (2019), employing different operationalizations of phraseological sophistication, each representing a different conceptualization of the dimension. To conclude, I will outline what I regard as the most pressing avenues for future research into phraseological complexity and its construct validity