Background: African Americans have one of the lowest smoking rates as teens yet have one of the highest smoking rates as adults. Approximately 40% of African Americans who have ever smoked started smoking between the ages of 18 and 21. Purpose: This study aimed to identify why African American young adults began smoking in young adulthood and what personal, social, and environmental influences promoted the transition to regular smoking. Methods: Twelve focus groups were conducted with African American young adults (n = 99) between the ages of 18 and 29 who began smoking regularly after the age of 18. Results: Participants did not smoke while they were younger because of strong maternal antismoking messages, out of respect for elders, or because they smoked marijuana instead. Factors influencing smoking initiation were perceived smoking social norms, changing parental messages about smoking, believing that smoking was an adult coping strategy, and extending a marijuana high. Discussion: African American young adult smokers described multiple levels of influences on smoking initiation and the transition to regular smoking. Translation to Health Education Practice: Recommendations include continuing strong parental messages against smoking, preparing youth for the transition to young adulthood, targeting normative smoking beliefs, and delinking smoking from marijuana use.