This two-part paper presents a comprehensive case study related to the development and evaluation of warning labels. In particular, this two-part paper describes the development and evaluation of revised warning labels applicable to a class of products known as personal watercraft (PWCs), and serves as an example application of a general warnings design process described by Frantz et al. Part 1, presented in this paper, includes the process of project planning, identifying and analyzing hazards, and developing two preliminary warning labels to address PWC operational hazards. Included are discussions regarding the methods used to address problems frequently encountered in the development of warning labels. Topics of these discussions include the prioritization and selection of hazards to be addressed, message development strategies, avoiding information overload, and organizing the presentation of information using human factors models and concepts. The work conducted in Part 1 resulted in two preliminary labels: one label dealing with issues related to Collision Avoidance and a second label dealing with General Operational Hazards. Part 2, the companion article, describes the process of evaluating and revising the preliminary labeling to produce the final labels. Discussions regarding the methods used to address challenges related to the evaluation and revision of warning labels are provided. As a result of the entire process, revised labels for PWCs with increased uniformity will be used by PWC manufacturers, although flexibility for specific model features or future changes in design will be retained.