Objective: Numerous effective tailored interventions for smoking cessation and other behaviors have been developed based on the Transtheoretical Model. Recent studies have identified clusters within each stage of change. The goal of this study is to determine if replicable clusters exist within the Preparation stage of change for sun protection. Method: Secondary data analysis of baseline data from a sample of participants in a home-based expert system intervention was performed. Two random samples of approximately 128 participants were selected from subjects in the Preparation stage (N = 258). Cluster analyses were performed using Ward's Method on the standardised scores from the three scales of Pros, Cons, and Self-Efficacy. Interpretability of the pattern, pseudo F test, and dendograms were used to determine the number of clusters. Results: A four-cluster solution replicated across subsamples. Differences between clusters on eight of the nine Processes of Change, and on behavioral measures, were found. Discussion: The cluster solutions were robust, easily interpretable, and demonstrated good initial external validity. They replicated patterns found for other behaviors that have demonstrated long-term predictability and can provide the basis for a tailored intervention.