Persons with mental illnesses such as schizophrenia may internalize mental illness stigma and experience diminished self-esteem and self-efficacy. In this article, we describe a model of self-stigma and examine a hierarchy of mediational processes within the model. Seventy-one individuals with serious mental illness were recruited from a community support program at an outpatient psychiatry department of a community hospital. All participants completed the Self-Stigma of Mental Illness Scale along with measures of group identification (GI), perceived legitimacy (PL), self-esteem, and self-efficacy. Models examining the steps involved in self-stigma process were tested. Specifically, after conducting preliminary bivariate analyses, we examine stereotype agreement as a mediator of GI and PL on stigma self-concurrence (SSC); SSC as a mediator of GI and PL on self-efficacy; and SSC as a mediator of GI and PL on self-esteem. Findings provide partial support for the proposed mediational processes and point to GI, PL, and stereotype agreement as areas to be considered for intervention.