Background: Tobacco industry practices contribute to the tobacco epidemic globally, particularly in low- and middle-income countries. People are often unaware of how tobacco industry practices prevent the enactment of tobacco control policies and contribute to harm. The aim of this study is to identify what messages are most likely to build public awareness, trigger anger and outrage, and lead to two behaviors: increased information seeking and calls to hold the industry accountable. Six messages were developed and tested about the tobacco industry’s activities, with these themes: (1) environmental harms caused by littering; (2) environmental harms related to farming and livelihoods; (3) tactics that lead youth to addiction; (4) the need to pay for damages during COVID-19; (5) child labor practices; and (6) the use of junk science to manipulate policy.

Methods: Message effectiveness was assessed among 980 adults ages 18 to 55 years in India, South Africa and Brazil. A standardized message rating survey, including a mix of quantitative and qualitative measures, was conducted with purposively selected online samples. Chi-square tests with quantitative data, and inductive thematic analysis with the qualitative data, were performed.

Results: Across countries, messages that described child labor practices and environmental harms caused by littering were deemed most effective in motivating participants to seek information about tobacco industry practices and hold the industry accountable. The message about youth addiction received mixed ratings: some participants found the ad convincing, while others felt youth would continue to vape after viewing the ad. The message suggesting the tobacco industry should pay for damages during COVID-19 consistently performed lowest for message effectiveness.

Conclusions: Environmental and child labor messages are most motivating to take action. The consistency of results from three geographic locations suggests how this study’s findings may inform efforts across diverse markets to communicate about tobacco industry exploitation.