Purpose: To create a psychometrically sound scale that measures different levels of internalized stigma (i.e., self-stigma) among adults who stutter and to analyze factor structure, reliability, and initial construct validity of the scale. Method: Two-hundred ninety-one adults who stutter were recruited from Board Recognized Specialists in Fluency Disorders and the National Stuttering Association. Participants completed a web-based survey including an experimental scale called the "Self-Stigma of Stuttering Scale" (4S), designed to measure different levels of self-stigma in people who stutter, along with a series of established measures of self-esteem, self-efficacy, and life satisfaction. Results: The experimental scale demonstrated adequate reliability in internal consistency and temporal stability. Factor analysis revealed underlying components supportive of a multidimensional model of stigma. Stigma self-concurrence and, to a lesser extent, stereotype agreement and stigma awareness were negatively correlated with self-esteem, self-efficacy, and life satisfaction, supporting initial construct validity of the scale. Conclusion: Speech-language pathologists can identify the presence of self-stigma in their adult clients who stutter and help them to alter these beliefs. The 4S can be a means for researchers and clinicians to achieve these goals.