Background: Preventing the spread of COVID-19 requires the modification of behavior, including social distancing, mask-wearing, and regular handwashing. Modifying behavior requires understanding people's knowledge, attitudes, and practices (KAPs) regarding health threats. We explored KAPs among Colombians to examine whether KAPs affect adherence to recommended practices during the initial outbreak. Methods: We distributed a cross-sectional, internet-based questionnaire using referral network techniques. The questionnaire addressed three areas: knowledge about COVID-19; attitudes toward the ability to control it; and, self-reported practices related to the control of COVID-19. Demographic data were also collected. Results: A total of 482 individuals completed the questionnaire. Participants had low to moderate levels of knowledge about COVID-19. They expressed mixed levels of optimism about the world eventually controlling COVID-19, but they were very optimistic about Colombia's ability to control the disease. They reported extremely high levels of adoption of preventive practices. Binomial regression suggests few demographic factors associated with KAPs. Generally, knowledge had no association with optimism and little association with self-reported adoption of recommended practices. Conclusions: These findings indicate that greater knowledge of COVID-19 is insufficient to prompt behavior change. Colombians' greater optimism about their own country's ability to overcome COVID-19 as compared to the world's ability should be explored in greater depth. Since attitudes are associated with actions, future investigation of Colombians' optimism may provide guidance for improving attitudes elsewhere. Because adoption of preventive practices is extremely high in Colombia, Colombia may serve as a model case for how other nations can respond to COVID-19.