Immigration scholars have demonstrated the increasing importance of transnational activities among contemporary immigrants. While much of the previous research has emphasized social and economic outcomes, very little attention has been paid to psychological well-being or mental health. Using a community sample of West Indian immigrants, we developed an empirical measure of the nature and frequency of transnational practices. The resulting Transnationalism Scale is examined for psychometric properties using an exploratory principal components factor analysis, and bivariate correlations with pre-existing measures of psychological well-being, perceived social support, and ethnic identity. Results reveal five factors, some of which are significantly correlated with measures of psychological well-being, social support, and ethnic identity. Findings suggest that transnationalism, as a construct, is a valid measure for this population. We argue that transnational ties shape various aspects of immigrants' lives.