<p>The effectiveness of behavior analytic interventions and scientific investigations rests on the validity and accuracy with which practitioners and researchers define and measure behaviors. Experts widely recommend using operational definitions to define behaviors. However, researchers have yet to extensively document an empirical investigation on developing operational definitions. Instead, practitioners have relied on textbooks to provide a shared understanding of the commonly used general guidelines. The current study investigated how behavior analysts operationalize behaviors by having respondents develop operational definitions for two behaviors displayed in short video recordings. Statistically significant associations between respondent characteristics and definitional components use were limited, suggesting that various behavior analysts' characteristics that were analyzed (e.g., certification level, years of experience, client population) did not affect how behavior analysts generated different components of operational definitions. Implications, recommendations for future investigations, and limitations are discussed.</p>