Recent increases in maternal cannabis use, in combination with rapidly changing cannabis policies in the United States, pose a unique threat to maternal and child health. To date, 33 states and the District of Columbia (D.C.) have legalized medicinal cannabis, and 11 states and D.C. have legalized recreational cannabis. Many other states have decriminalized cannabis and are considering legalization. Recent data suggest that maternal cannabis use is increasing. Maternal cannabis use in the postpartum period, including breastfeeding women, may contribute to negative health outcomes in young children. Perinatal health professionals should work collaboratively to safeguard maternal and child health outcomes from potential adverse health effects of cannabis use. To that end, we highlight the critical role certified lactation consultants (CLCs) could play in postpartum management of cannabis use. CLCs have direct access to a large number of women shortly after delivery and throughout the postpartum period. They are an extremely well-positioned, but arguably underutilized, and are potential partners for postpartum management of cannabis use. Given the rapport CLCs frequently develop with their patients, these mothers may be especially willing to disclose cannabis use and be receptive to education and advice to quit cannabis use while breastfeeding. As such, we propose that the role of CLCs be promoted to support families with nonpunitive education about the potential risks, advice to not use cannabis while breastfeeding, and timely referral for treatment, when needed. This approach holds promise for improving the health and quality of life for breastfeeding women and their infants.