Globalization has produced increasingly multicultural workplaces, resulting in a proliferation of cross-cultural difficulties for expatriate employees and their work organizations. Expatriate workers often experience high levels of stress, and because of this, the rate of mental ill-health among expatriates is increasing. The review argues that examining psychological adjustment can advance our understanding of the role of mental health in expatriate success. Thus, this review first examines the prevalence and significance of measuring the psychological adjustment dimension among multinational corporation (MNC) expatriate workers in the cross-cultural literature. Second, this review examines the role of cross-cultural training (pre-departure and post-arrival) and its effectiveness on expatriation success. This review analyzed 22 empirical studies published between 1994 and 2020 that examined either or both: (1) cross-cultural adjustment, emphasizing the psychological adjustment component, and (2) cross-cultural training, emphasizing the effectiveness and impact of pre-departure and post-arrival cross-cultural training on long-term expatriation success among MNC expatriate workers. This review was conducted with a specific goal of increasing our understanding of the role of psychological adjustment and how appropriate cross-cultural training may increase expatriate success.