This nonrandomized pilot study is investigating the efficacy of a modularized treatment for anxiety in children ages 3-7 years old. Eligibility is determined at a baseline assessment, followed by a second baseline assessment one month later. The treatment protocol, Parent-training Intervention for Preschoolers with Anxiety (PIPA), is flexible and allows for individualized treatments based on a treatment algorithm, ensuring that sessions address the most pressing clinical needs of each child. Treatment consists of weekly 60-minute sessions delivered over the course of 12 weeks. Symptom change is tracked weekly during brief phone assessments and a post-treatment assessment will occur following the final treatment session, approximately 12 weeks after starting treatment. Finally, all participants will complete two follow-up assessments, occurring 1-month and 6-months after the final treatment session.

Early childhood mental illness is a growing public health concern, and can persist into adolescence and adulthood if left untreated. Anxiety disorders are among the most common psychiatric illnesses in preschool aged youth and place youth at significantly higher risk for anxiety, depression, substance abuse, conduct problems, and diminished academic/occupational and social/relational functioning later in life. Accordingly, there is increasing emphasis on early identification and intervention, before symptoms become entrenched to mitigate a trajectory towards longstanding impairment.

Unfortunately, empirically supported treatments for preschoolers with anxiety are limited. The few studies to date have tended to focus on relatively homogeneous samples whose symptoms resemble those in adults (e.g., worries and fears). Anxiety can present in similar ways to adult anxiety, however can also present more broadly in young children. Young children with anxiety may also present with extreme rigidity, sensory hypersensitivity, 'meltdowns'/emotional dysregulation/temper tantrums, ritualistic/routine oriented behavior, and oppositional behavior in some context. By focusing narrowly, treatments have not been adapted for the full range of anxiety presentations in early childhood.

Therefore, the proposed study evaluates a modular, parent-driven psychotherapy developed for preschool aged youth (3-7 years) with diagnostic levels of anxiety, as well as anxiety symptoms dimensionally. The treatment program, Parent-training Intervention for Preschoolers with Anxiety (PIPA), is based on empirically supported behavioral and parent-training principles as well as the investigators' recently published pilot study of preschoolers with obsessive compulsive disorder. Sixty youth will be treated during the study. PIPA focuses on exposure and response prevention therapy (E/RP) in the context of behavioral parent training, each of which have efficacy in youth with anxiety, including high functioning autism spectrum disorders (ASD). Certain parenting responses (e.g., overprotection, critical responding, accommodation of anxiety symptoms and avoidance) have been implicated in the etiology and maintenance of pediatric anxiety disorders and, in addition to E/RP, this intervention will target behavioral parent training and unhelpful parenting practices to support long-term outcomes.

In addition, this study will investigate one surrogate biomarker of anxiety in young children, fear conditioning (or more specifically, resistance to extinction). Behavioral treatment of anxiety, including the proposed PIPA intervention, relies on principles of extinction. Children and adults with anxiety disorders have been shown to have poorer fear extinction; however, there are few studies in young children examining this phenomenon. The potential to understand fear extinction in young children has implications for improving treatment efficacy and altering the negative trajectory of youth with anxiety disorders.

Eligibility will be determined at a baseline assessment. A second baseline assessment will occur one month later for those that qualify. This assessment will be used to control for symptom change due to the natural passage of time. Treatment will be delivered over 12 weeks and will include weekly 60-minute sessions. A brief phone call with an assessor each week will be used to track symptom change during treatment, and a post-treatment assessment will be conducted following the final treatment session, approximately 12 weeks later. Follow-up assessments will occur 1-month and 6-months following the final treatment session.

Inclusion Criteria:

• Children aged 3 to 7 years
• Anxiety-based concerns rated as a top problem on the Top Problems Assessment at initial assessment.

Exclusion Criteria:

• Report or evidence of severe intellectual disability or level 3 autism spectrum disorder (ASD) without accompanying intellectual/language impairment (mild ASD is not exclusionary).
• Presence of clinical features requiring a higher level of care (inpatient or partial hospital treatment).
• Unwillingness of parents to accompany their children for multiple study visits;
• Presence of a significant and/or unstable medical illness that might lead to hospitalization during the study.
• Initiation of an antidepressant within the 12 weeks preceding study enrollment, antipsychotic within 8 weeks prior to study enrollment, changes in established psychotropic medications within 8 weeks before study enrollment, or any change in alternative medications that might have behavioral effects within 6 weeks prior to study baseline assessment. Youth may remain stable on medications during the study.
• Ongoing reports of abuse/neglect or trauma reported as a primary concern.
• Extreme aggression/risk behaviors (e.g., harming animals, fire starting, violence) suggestive of conduct disorder trajectory.