An emerging finding in the narrative identity literature is that, within the context of a longitudinal study in which narrative measures are administered repeatedly, most participants recognize different self-definitional events across tellings. In this article, I offer 4 possible explanations for the between-person variability observed in this self-definitional event temporal stability (SETS). Each possibility is then explored via the analyses of the 4 cases considered in this special issue of Qualitative Psychology. Among the 4 possibilities introduced, the most support was gathered for the notion that (a) those who demonstrate lower levels of SETS have experienced more significant life events between assessments, compared with those high in SETS (derived from the observation that, in their second interview, the low SETS cases narrated a greater number of events that had occurred since their initial study participation, when compared to the high SETS cases); and (b) extraversion (a personality trait defined by assertiveness, sociability, and energy level) accounts for between-case variability in SETS (derived from the observation that the low SETS cases had higher levels of extraversion than the high SETS cases). These findings are discussed in relation to narrative identity theory, traits, and the integration of these 2 paradigms of personality psychology. (PsycINFO Database Record (c) 2019 APA, all rights reserved)