Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by challenges in socialization and communication, and restricted, repetitive behaviors or interests across development (American Psychiatric Association [APA], 2013). Youth with ASD have an increased risk for developing anxiety disorders (Mattila et al., 2010). Anxiety in youth with ASD is associated with further socialization and communication impairment (Duvekot et al., 2010), behavioral issues (e.g., conduct problems, hyperactivity, inattention; Farrugia & Hudson, 2006), and emotional issues (e.g., self-injurious behavior, depression symptoms; Kerns et al., 2015). Effective anxiety interventions for this population are therefore needed due to the widespread impairment associated with anxiety (Chang et al., 2012; Duvekot et al., 2018; Kerns et al., 2015). Research shows that cognitive behavioral therapy (CBT) is an effective intervention for children with ASD and anxiety (Ung et al., 2015); however, barriers to implementing CBT exist, such as the distance and limited transportation to services (Stewart et al., 2017). These treatment barriers can be addressed via teletherapy. Moreover, Social Stories[superscript TM] can be easily implemented via the computer (Sansoti & Powell-Smith, 2008). They have been included in CBT programs for children with ASD and anxiety but have not been used as the main intervention (Ooi et al., 2008; Schleismann & Gillis, 2011; Sofronoff et al., 2005; Sung et al., 2011). The current study examined the efficacy of an internet-based Social Story intervention for anxiety that includes aspects of CBT found effective in previous research (Hepburn et al., 2016; Schleismann & Gillis, 2011; Ung et al., 2015; Wise et al., 2019; Wood et al., 2009). For the present study, participants were six children between 8 and 12 years old diagnosed with ASD and an anxiety disorder. They were recruited from Hofstra University's Diagnostic and Research Institute for Autism Spectrum Disorders and local support groups for parents of children with ASD. Parents of participants also participated by observing sessions and implementing the intervention's homework assignments. It was hypothesized that from baseline to treatment, the intervention would contribute to decreased child anxiety levels, decreased child behavior avoidance, decreased parental stress, increased child self-efficacy and increased parental self-efficacy, based on parent- and self-reports. Additionally, it was hypothesized that these improvements would be maintained across a 2-week maintenance phase. A small-"n," multiple baseline design was used to investigate data across the intervention's 3-week baseline phase, 6-week treatment phase, and 2-week maintenance phase. Data was analyzed using visual analyses, percentage exceeding the median (PEM; Ma, 2006), and standard mean difference (SMD; Busk & Serlin, 1992). Dependent Samples T-Tests were used to determine if treatment effects were maintained across the 2-week maintenance phase. Further, a time series analysis explored the relation among self-efficacy, anxiety, and parental stress. Results showed that each participant improved in at least one of the aforementioned variables, with most participants improving in their child-reported anxiety levels. Implications for future research, as well as the strengths and limitations of the study, are discussed. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]