Mindfulness is typically described as bringing attention to thoughts, feelings, and bodily sensations in the present moment. There is evidence for cross-cultural differences in concepts of mindfulness, though little research has examined the content of these diverse concepts. More research is needed to investigate concepts of mindfulness in non-Western and non-Eastern cultures. Fieldwork observations suggest that religious and traditional cultural practices support mindfulness in Uganda. Christianity has become widespread in Uganda, but Christian beliefs and worldviews are often integrated with traditional, pre-colonial worldviews and practices. The present research aimed to systematically compare mindfulness concepts between Ugandan Christian and American Buddhist meditators. The primary method employed was a cognitive interview in which participants completed the Five Facet Mindfulness Questionnaire (FFMQ) while providing open-ended think-aloud descriptions of thoughts about each item. The open-ended responses were coded, and frequencies of codes within each subscale of the FFMQ were analyzed. Comparisons of Likert-scale responses showed that Americans scored significantly higher than Ugandans on the subscales that measured capacities for describing thoughts or feelings and viewing one's present-moment experience without judgment. Analyses of responses to open-ended questions showed that Ugandans were significantly more likely than Americans to relate their mindfulness experience to interactions and relationships with others, spirituality, and a value for discernment, and that Americans were significantly more likely than Ugandans to talk about progress in their mindfulness practice. Although Ugandans were more likely than Americans to talk about relationships with others as part of their mindfulness experiences, participants in both cultural groups provided evidence for positive correlations between concepts of others, spirituality, judgment, and practicing mindfulness. The findings suggest that these constructs are important components of mindfulness that deserve further research.