The present study employed a mixed methods approach to explore well-being, quality of life and experiences among Japanese sojourner graduate students studying in the U.S. utilizing 155 survey responses and 39 in-depth individual interviews. Key measures used include: the K6 screen for risk of serious mental illness (K6) (Kessler et al., 2002), the short version of the World Health Organization Quality of Life (WHOQOL-BREF) (WHOQOL Group, 1998), the Family Health Status Inventory (NISI) (Norem, Malia, & Garrison, 1988), the Interethnic Contact Scale (Stephan & Rosenfield, 1978), the Multidimensional Scale of Perceived Social Support (MSPSS) (Zimet, Dahlen, Zimet, & Farley, 1988), and the Suinn-Lew Asian Self-Identity Acculturation Scale (SL-ASIA) (Suinn, 1998). The major findings include: (1) a significant portion of participants (13%) were at significant risk of serious mental illness, which is more than four times higher than the general population in Japan and the U.S.; (2) despite the high risk of serious mental illness, most students reported high quality of life, though students at risk of serious mental illness had significantly lower quality of life; (3) being female, lacking perceived social support from a special person and friends, lower degree of values aspects of acculturation were significantly associated with higher risk of serious mental illness; (4) being female, lacking perceived social support from a special person and friends, lower degree of both behavioral and values aspects of acculturation were significantly associated with lower quality of life; (5) the perceived social support from friends had a greater buffering effect for participants with weaker belief in Western/U.S. values in predicting both risk of serious mental illness and quality of life; (6) while both male and female students who perceived higher psychological stress in the U.S. than in Japan reported loneliness/isolation, language difficulties and feelings of marginalization in the US society as major challenges they faced, the specifics of these challenges appear to have been deeply affected by gender. This study offers implications for developing effective pre-departure and on-site orientations, counseling sessions and support mechanisms for international students. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]