Japan, similar to the rest of the world, faces the complex process of rapid and profound demographic and socio-economic changes (Matsumoto, 2002; Kingston, 2004; Roach, 2009), challenging the established and time-honored attitudes and perceptions of social and intimate relationships, public and private spheres, as well as social support networks (Quah, 2008). Japan, along with other Asian countries is undergoing such a dramatic social shift that many academics, policy makers and other public figures express concern for the future of coming generations (Kingston, 2004; Chan, 2004).

The common feature is growing transnational and transcontinental migration due to the globalization process (Vogt, 2007; Naohiro, 2001), followed by increased cross-cultural awareness. As a result, Japan witnesses an influx of ‘newcomers’ and growing transnational migration movements (Kashiwazaki, & Akaha, 2006; Kingston, 2004), which may be highly beneficial, offering acculturation options between multiculturalism and melting pot (Berry et al., 2002), as well as adding a transitionally destabilizing factor to Japanese society, as some studies point it out, depending on the social capital processes taking place internationally and domestically, like segregation and exclusion (Berry et al., 2002; Vogt, 2007).

Migration is being fueled for various reasons. It may depend on more general factors, such as the geopolitical, economic and demographic profiles of the country of origin (Vogt, 2007), as well as individual conditions such as previous travelling experience, language proficiency, previous exposure to the host country’s culture and people, mass media, educational level, and finally personal aspirations, plans, or dreams related to the move (Friedlmeier, Chakkarath, & Schwarz, 2005; Kingston, 2004).

Migrants coming to Japan often face the acculturation process (Berry et al., 2002), regardless of the individual set of factors leading to the decision of settling down in Japan. This acculturation process may include different strategies and outcomes, some of them offering personal growth and social competence (assimilation, integration) offering both a newcomer and the host country mutual social benefits and enriching social capital of Japan. On the other hand, some acculturation strategies are associated with a high risk of negative outcomes, resulting in separation, marginalization, frustration, and alienation (Shiraev, & Levy, 2007; Berry et al., 2002).

The research analysis of acculturation strategies and Japanese society’s response to newcomers may be highly desirable about the rapid and profound demographic and socio-economic changes in Japan. The implementation of social science research methodology, as well as cross-cultural and trans-disciplinary studies, is viewed as significantly advantageous in the study of social stratification and inequality, offering deep and multi-layered analysis.

When analyzing Japanese society, there is unquestionable data supporting the thesis about its aging population (Raud, Sakuragawa, & Goto); visible changes in lifestyles and culture (Matsumoto, 2002; Kanda, Kimura, & Noguchi, 1992; Davies, & Ikeno, 2002); changing sexual expressions and dating patterns among young people (Yamamoto, 2008; Saotome, 2010) – for instance, the high rise of never-married persons, as well as the emergence of so called ‘herbivorous’ young men (Fukasawa, 2009; Gosselin, 2010); and even the increasing number of dating agencies targeted at foreigners as prospective husbands and wives, promoted in the popular publications (Iwama, 2007), etc. What is more, there is an alarming marriage breakdown between Japanese couples (Jones, 2009), drastically reduced fertility rates (Quah, 2008), increased divorce rates (Imamura, 1990; Jones, 2005), and emerging alternative family patterns (Raymo, Iwasa, & Bumpass, 2008).

Contrary to the above data, there is a noticeable growing frequency of international marriages among the Japanese population – in spite of the downward trend in marriage between Japanese couples. The data shows a continuous rise in the number of international marriages – Kokusai kekkon, reaching 34,393 in 2009, which translates approximately to 1 in 20 married couples in Japan (Yamamoto, 2010).

These marriages draw psychological, sociological and anthropological attention: firstly, as a striking counter-trend to the overall decreasing number of marriages in Japan (Yamamoto, 2010; Fumiteru, 1988), and secondly, because of very limited psychological data of family dynamics, parenting attitudes and styles, and the acculturation process taking place in the international couples in Japan.

There is some available data about the profile of international marriages (Nitta, 1988), showing highly gendered patterning, where 78% of international marriages registered in 2009 in Japan were between a Japanese man and foreign woman (Yamamoto, 2010), or interesting trends represented by different nationalities (Chinese, Korean, Filipino brides vs. American, Australian, European grooms, as desired partners by the Japanese). However, the whole picture seems to be blurred, only allowing for very vague interpretation. What is more, the data, although very valuable, does not fully explore the family communication patterns, personality traits, and matching strategies, couple social contacts in macro scale, and as a result, the available findings are open to biased interpretation and stereotyping, and even pejorative social perception: for example, negative connotations of economic motivations regarding Asian, non-Japanese brides (Yamamoto, 2010), or in the case of Japanese women who decide to marry Western men, as the choice of a new „life-style‟ or „modern husbands and modern marriages‟ trendy option (Yamamoto, 2010).

There are crucial questions that arise from the discussion presented above, regarding the deeper psychological and mating mechanisms lying beneath the Kokusai kekkon phenomenon.

First, what motivates the Japanese turning to foreigners as prospective husbands or wives, and from the foreigners’ perspective, what kind of expectations and predictions they make when deciding to marry a Japanese national?
Second, what happens next in terms of the acculturation process, followed by parenting and social involvement in community and broader society?

Third, can we establish a set of personality traits and behavioral patterns, in both Japanese and non-Japanese partners, regarding the decision of entering Kokusai kekkon?

The other factor involved that deserves scholarly attention is linked to children of mixed couples. Yamamoto (2010) presents data showing that approximately up to 25 thousand children have been born each year to the international couples. So far we know little about the cultural heritage, cultural identity, and self-perception of these children, as well as the peer interactions at school and in a broader social context.

This research program would be potentially beneficial and aiming to deliver the applied framework for the present and future reconstruction and enrichment of public and intimate spheres in Japan. First, the program would be focused on the Japanese, and the delivery of efficient strategies supporting the development of cross-cultural competency. Second, the investigation of foreigners marrying Japanese citizens, their motivations, aspirations, attitudes and adaptations, may results in offering the sociological niche in Japanese society for the migrants in Japan.

This short introduction to the current issues in Japanese society is just an attempt to draw attention to significant trends and offer suggestions for future research.