Objective: In the USA, organ donor shortage is especially pronounced among minority ethnic populations such as Hispanics, who are 60% less likely to donate compared to non-Hispanic Whites. Recent evidence suggests that US Hispanics may consent to organ donation via a registry within a doctor's office. The objective of this study was to investigate the effectiveness of using "kiosks" to distribute organ donation educational material located within primary care clinics on US Hispanic donor registration rates. Design/setting: A prospective observational study was conducted at four clinics, located in Southern Californian neighbourhoods with a high percentage of Hispanics. Method: Kiosks containing organ donation educational material were set up at each clinic for a total of 7 weeks. The kiosks were unstaffed for 6 weeks, 3 weeks before and 3 weeks after a week that was staffed by individuals from OneLegacy, the local Organ Procurement Organisation (OPO). The number of patient encounters and the number of patients who registered were recorded and analysed. Registration rates per 1,000 patient encounters and 95% confidence interval (CI) were derived. Differences between the staffed and unstaffed kiosks were assessed. Results: During the 6-week unstaffed period, a total of 59,181 patient encounters occurred with a registration rate of 0.03 per 1,000 (95% CI: 0.0-0.1). During the 1-week staffed period, a total of 9,805 patient encounters occurred and 102 patients registered, which is a registration rate of 10 per 1,000 (95% CI: 8-13). Significance was reached when comparing staffed and unstaffed rates of registration (p < 0.0001). Conclusion: This study demonstrates that when compared with unstaffed kiosks, staffed kiosks are more effective in increasing organ donation registration among US Hispanics.