This study examined the problems and challenges of social and academic integration in U.S. higher education institutions for Saudi Arabian and Mexican undergraduate international students. The purpose of this quantitative, cross-sectional, descriptive, and causal-comparative study was to examine the relationship among a) demographic variables (i.e., age, gender, education, marital status, nationality, and previous academic performance), b) academic integration, c) social integration, and d) intent to drop out among Saudi and Mexican students studying at U.S. colleges and universities. In addition, the study compared whether Saudi and Mexican female students were less integrated academically and socially than their male counterparts. Previous studies examined the challenges of social and academic integration for domestic and international university students in the U.S. (Al-Dayel, 2018; Stadtfeld et al., 2019). Additionally, previous research has focused on understanding how social and academic integration challenges affected international students from specific nations or territories (Arambewela & Hall, 2009). However, this prior research focused on one nationality of international students rather than comparing multiple nationalities. Limited studies have compared the challenges in social and academic integration for different nationalities of international students attending U.S. institutions to determine if social and academic integration may affect students from various countries differently. Thus, this study fills a gap in the literature by comparing sample groups of Saudi Arabian and Mexican international students who attend universities in the U.S. and their experiences in connection to social and academic integration challenges. The research questions explored whether or not the independent variables were associated with academic and social integration scores and if social and academic integration predict students' intent to drop out among Saudi and Mexican students. The researcher sought to understand if academic and social integration moderated relationships between demographic variables and dropout intentions. These questions were important because of the increasing economic importance of integrating international students into the U.S. higher educational system (Baer, 2017; Cong, 2017). Colleges and universities in America benefit when they safeguard the retention of their international students. This study provides insight into factors that influence international students' experiences. The data collection method was a quantitative, self-administered web-based survey sent to Saudi and Mexican international students in U.S. universities. The survey consisted of a demographic questionnaire, two subscales measuring academic and social integration, and a scale measuring dropout intention. Other researchers validated all scales and subscales and were also examined for reliability in this study using Cronbach's alpha and showed acceptable reliability scores. Data analysis included descriptive statistics, independent samples t-tests, and multiple linear regressions. The findings indicate age was the only variable statistically significant and was negatively associated with academic integration, not social integration, and this was only true for Saudi students. Notably, there was not a statistically significant association between other demographic variables and social or academic integration for Saudi or Mexican undergraduate students in this study. Further, there was no statistically significant relationship between academic and social integration and intent to drop out in the sample of Saudi students. Conversely, there was a statistically significant relationship between academic and social integration and student intent to drop out in the Mexican student sample. Additionally, there was a statistically significant relationship between nationality and academic integration, where Mexican students had higher levels of academic integration than Saudi students. This study used Tinto's (1993) model of integration to examine Saudi and Mexican undergraduate students. Key demographic variables, such as age, gender, years living in the U.S., marital status, and previous academic performance, do not lead to social and academic integration, higher performances, and lower dropout intention. These findings suggest that other more complex factors--not accounted for in the Tinto model--could play a role in these relationships. For example, more expansive social change variables should be integrated into the model to capture the complexity among Saudi and Mexican international students studying in U.S. higher educational institutions. It is an area where future study may better identify independent variables more specific to the populations or consider social integration outcomes within other contexts for international students (including perhaps graduate-level learners). The social changes occurring among Saudi and Mexican students were more homogenous than divergent, and the integration experiences between the two groups were more similar than the hypotheses suggested. This result indicated that American universities in this sample may have been more responsive than hypothesized in their efforts to integrate international students at their institutions. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. 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