The present study examined the relationship between initial youth hope, measured within the first 4 weeks of mental health treatment, and treatment progress over time (self-, caregiver-, and clinician-report of symptom severity) in a clinical sample of youth ages 11-18 years (N = 356). The psychometric properties of the CHS-PTPB, a revised version of the Children's Hope Scale, are also presented. Results indicate the CHS-PTPB is a psychometrically sound measure for use in this population. Additionally, results found that while higher levels of hope were associated with lower levels of symptom severity at baseline, initial level of hope was not significantly related to symptom improvement over time as reported by the youth and caregiver. Surprisingly, higher initial hope predicted slower treatment progress as rated by clinicians. According to clinician-rated symptom severity, youth with high initial hope and high baseline symptom severity show the poorest predicted clinical outcome. Implications, future directions, and limitations of the study are discussed.