Objectives: To examine the phenomenon of non-smokers spontaneously taking action to seek help for smokers; to provide profiles of non-smoking helpers by language and ethnic groups. Setting: A large, statewide tobacco quitline (California Smokers' Helpline) in operation since 1992 in California, providing free cessation services in English, Spanish, Mandarin, Cantonese, Korean, and Vietnamese. Subjects: Callers between August 1992 and September 2005 who identified themselves as either white, black, Hispanic, American Indian, or Asian (n = 349 110). A subset of these were "proxies": callers seeking help for someone else. For more detailed analysis, n = 2143 non-smoking proxies calling from October 2004 through September 2005. Main outcome measures: Proportions of proxies among all callers in each of seven language/ethnic groups; demographics of proxies; and proxies' relationships to smokers on whose behalf they called. Results: Over 22 000 non-smoking proxies called. Proportions differed dramatically across language/ethnic groups, from mean (+/- 95% confidence interval) 2.7 (0.3)% among English-speaking American Indians through 9.3 (0.3)% among English-speaking Hispanics to 35.3 (0.7)% among Asian-speaking Asians. Beyond the differences in proportion, however, remarkable similarities emerged across all groups. Proxies were primarily women (79.2 (1.7)%), living in the same household as the smokers (65.0 (2.1)%), and having either explicit or implicit understandings with the smokers that calling on their behalf was acceptable (90.0 (1.3)%). Conclusions: The willingness of non-smokers to seek help for smokers holds promise for tobacco cessation and may help address ethnic and language disparities. Non-smoking women in smokers' households may be the first group to target.