Emotional and behavioral problems, like anxiety, mood disorders, disruptive behaviors, and irregular sleep and eating patterns, often accompany autism. If researchers better understood the nature and rates of occurrence of these problems, they should be able to manage the problems more effectively, and they also might be able to identify subgroups of children with similar problems whose autism has a similar course and severity. Subgroup identification would enable researchers to determine whether children in each subgroup have any common genetic factors associated with these patterns of the disease. The Duke University researchers previously developed an assessment tool that identifies effects and rates of behavioral and emotional problems in non-autistic children aged two through five. Now, the investigators will collaborate with autism researchers to adapt the current assessment tool to autism. The newly developed version of the tool will be evaluated in 100 participating parents of children with autism to determine the tool's reliability (its ability to repeatedly elicit the same person's response to the same question) and its validity (effectiveness, compared to less detailed measures currently used) to identify children's psychiatric problems. Based on the preliminary information derived, the researchers also will provide initial data on the nature and rates of co-existing behavioral and emotional problems in their autistic children. These rates will be compared to those obtained previously for non-autistic children. Through this process, the researchers will determine the utility of the new tool, and provide initial subgroup categorizations of the children for further studies. Significance: Developing a new tool to determine coexisting emotional and behavioral problems in children with autism is anticipated to lead to better interventions to manage these constellations of problems. The research also may lead to the identity of genes associated with subgroups of children with autism, based on their co-existing psychiatric problems.