Abstract
Minority stress remains pervasive in various aspects of life among sexual minorities. Driven by the awareness of social injustice, some sexual minority individuals may undertake collective action to counteract discrimination, but this does not apply to all members of sexual minorities. The present study used a prospective, longitudinal research design to examine how different dimensions of minority stress (i.e., perceived discrimination and internalized stigma) interact to affect group identification and collective action. A total of 628 sexual minority individuals in Hong Kong were involved in the study. The results showed that prior discriminatory experiences were positively associated with collective action at follow-up through increased levels of group identification and commitment to social justice. The moderating effect of internalized stigma was found in which perceived discrimination was not significantly related to group identification and collective action among those with high levels of internalized stigma. The study extends the literature on the rejection-identification model by understanding collective action as a form of group-level coping in the face of discrimination. It highlights the importance of fostering group identification, strengthening collective action, and mitigating internalized stigma among sexual minorities in psychological practice.