Individuals with developmental disabilities often engage in aberrant behavior, such as self-injury. Functional analysis methodology, developed by Iwata et al. (1982/1994), has proven useful in determining factors that cause individuals to engage in such behavior. The extent to which practitioners have made modifications to the original method is unclear. Authors have recommended best practices to use when conducting functional analyses to reduce the likelihood of unclear or incorrect results. The current study attempts to identify what modifications from the original functional analysis method clinicians and researchers are using. A secondary purpose is to determine if recommended best practices are being used. Data will be collected using the Functional Analysis Survey. A list of clinics and universities at which functional analyses are likely to be conducted will be generated from the Association for Behavior Analysis Annual Convention list of presenters in 2005. Those facilities that had individuals present symposia or posters under the Applied Behavior Analysis category will be contacted to determine if functional analyses are conducted there. If so, a senior clinician or graduate student will be asked to complete the survey.