Clinical trials of treatments for high-grade gliomas have traditionally relied on measures of response or time-dependent metrics; however, these endpoints have limitations because they do not characterise the functional or symptomatic effect of the condition on the person. Including clinical outcome assessments, such as patient- reported outcomes (PROs), to determine net clinical benefit of a treatment strategy is needed because of the substantial burden of symptoms and impaired functioning in this patient population. The US National Cancer Institute convened a meeting to review previous recommendations and existing PRO measures of symptoms and function that can be applied to current trials and clinical practice for high-grade gliomas. Measures were assessed for relevance, relationship to disease and therapy, sensitivity to change, psychometric properties, response format, patient acceptability, and use of self-report. The group also relied on patient input including the results of an online survey, a literature review on available clinical outcomes, expert opinion, and alignment with work done by other organisations. A core set of priority constructs was proposed that allows more comprehensive evaluation of therapies and comparison of outcomes among studies, and enhances efforts to improve the measurement of these core clinical outcomes. The proposed set of constructs was then presented to the Society for Neuro-Oncology Response Assessment in Neuro-Oncology Working Group and feedback was solicited.