Reductions in substance use tend to coincide with marriage, as both may occur during emerging adulthood. During the transition to marriage, it is possible that one's spouse may be the influence that causes the reduction in substance use. Data on participants (N = 471 couples) for this report are taken from a longitudinal study of early marriage. The objective of the current analysis is to determine if having a spouse who uses marijuana is associated with a greater likelihood of one's own use. Additionally, we are interested in spousal influence and cessation. The findings support spousal influence. Husbands are more likely to start using marijuana if their wives use marijuana, but the reverse is not true. Husbands also are more likely to stop using if their spouses do not use. During the transition into marriage, the drug use of one spouse does affect the other. However, this influence appears to be unidirectional, with wives influencing their husbands more often.