Heavy episodic drinking (HED) among college students remains a significant public health concern in the United States, particularly among first-year students. Parents have been identified as a protective factor in college students' drinking behaviors and past parent-based interventions have been successful at reducing HED. However, there are a limited number of parent-based alcohol prevention strategies and a general lack of research on parent-child communication about alcohol use among first-year college students, particularly from the parent perspective. The three studies included in this dissertation assist in filling this gap by examining parent-college student communication about alcohol from a parents' perspective and identifying implications for future parent-based interventions. Study 1 classified parents into segments based on constructs from the Theory of Normative Social Behavior (TNSB), differences in parents' perceptions of student's alcohol use, and content of communication. A modification of the TNSB was used in Study 2 to explore intrapersonal and interpersonal factors that moderate the relationship between parents' descriptive norms related to students' alcohol use and the breadth of topics covered when they communicate with their college student about alcohol. Finally, building upon the first two studies, Study 3 used the Model of Family Decision Making (MFDM) to provide a contextual understanding of parents' communication about alcohol with their first-year college student. Studies 1 and 2 used a web survey conducted in 2010, 2011, and 2012 with a random sample of parents of first-year college students (N = 890) at a large Midwestern university. Results of a K means cluster analysis from Study 1 identified three parent clusters using constructs from TNSB. In Study 2, hierarchical linear regression analyses were conducted to explore what constructs of TNSB predicted parents' communication about alcohol, including descriptive norms, injunctive norms, outcome expectations, communication efficacy, and perceptions of severity and susceptibility of the negative consequences associated with alcohol use for their student. The study found the relationship between descriptive norms and parents' communication was moderated by injunctive norms, outcome expectations related to communication, and parents' perceptions of their student's susceptibility to negative consequences associated with alcohol use. Study 3 used qualitative interviews to further explore parents' communication about alcohol with their first-year college student. Using MFDM as a guide, Study 3 found several factors influenced parents' communication about alcohol with their student including role, skills, social structure, awareness, norms, utilization of resources, and other constraints. While parents reported talking about appropriate drinking behavior, the negative consequences of alcohol use, family experiences with alcohol, and family values and rules related to alcohol with their student, they often presented mixed messages, such as identifying drinking underage as illegal, but also describing the behavior as "typical." Across all three studies, it was evident parents held misperceptions of other college students' drinking behaviors and were likely underestimating their own students' alcohol use. The studies in this dissertation provide further understanding of the frequency and content of this communication and provide insight on how theoretical constructs can guide future parents-based interventions.