The purpose of this study was to determine school nurses' working knowledge of autism spectrum disorders (ASDs). The current knowledge of school nurses was investigated by means of a mixed-method exploratory descriptive pilot study. Instrumentation included a scale that measured the knowledge of school nurses in regard to ASD, including medication usage and side effects, communication skills, safety issues, collaboration skills, and community resources. Survey results indicated that the majority of school nurses are knowledgeable about ASD, including symptomology and related medications. Results also suggested that school nurses are not as knowledgeable concerning communication skills, behavioral therapies, and safety issues. This study confirms a need for school nurses to enhance their knowledge of ASD, to familiarize themselves with the policy and health care networks that they collaborate with, and to communicate effectively with students, parents, educators, and community members in dealing with ASD. (Contains 4 tables.)