Background: Individuals with glioma endorse high fear of cancer recurrence or progression (FCR), yet existing interventional studies for FCR exclude glioma patients. Components of existing FCR interventions are not entirely translatable to those with glioma as they were designed for non-central nervous system (non-CNS) cancer populations with less risk for recurrence, minimal-to-no neurologic sequelae, and different sources of worry. Methods: A two-stage Phase I ORBIT Model process was employed: Phase Ia included consultation with international FCR experts and two advisory boards toward the development of an intervention targeting FCR in neuro-oncology. Recommendations resulted in a 6-module mindfulness-based cognitive-existential intervention: Results: Phase Ia results supported an individual- or dyadic-level intervention with an emphasis on the inclusion of caregivers, a focus on individuals affected by malignant gliomas, and strategies to address glioma-specific FCR hypervigilance symptoms. Our phase Ib trial demonstrated adequate rates of enrollment, measure completion, retention, and satisfaction; however, screening rates (successful screening of those interested) were lower among caregivers. Conclusion: Findings support continued optimization of