AbstractIntent on developing methods of evaluation of L2 study abroad (SA) programs relevant for the 21st century, this study centered on sixteen Generation Z undergraduates affiliated with two U.S. universities and enrolled in the same Parisian program. To mitigate previous methodological issues, the study aimed to provide a big picture evaluation of the selected program with a purposeful focus on variables characteristic of Gen Zers. To do so, it adopted an innovative mosaic approach entailing the simultaneous collection and comparison of a multiplicity of data across different domains of interest. The study shows how pre-existing relationships between oral quality, cultural readiness, psychosocial measures attributed to Gen Z, phone affinity and usage, and demographic/academic characteristics evolved as outcomes of SA. It confirms the complex mediation involved in oral and cross-cultural growth abroad by notably unveiling a mechanism of inertia at play in language and cultural development linked to academic choices made before but set in motion by SA. The study also establishes how students’ pre-existing anxiety decreased congruently with fear of missing out and shaped their SA experiences. Finally, it demonstrates how the meaning attached to the role of smartphones morphed into a more positive relationship linked to emotional regulation and productivity.