Abstract Introduction Providing balanced information that emphasizes clinical equipoise (i.e., uncertainty regarding the relative merits of trial interventions) and exploring patient treatment preferences can improve informed consent and trial recruitment. Within a trial comparing adjuvant radiotherapy versus active monitoring following surgical resection for an atypical meningioma (ROAM/EORTC-1308), we explored patterns in communication and reasons why health practitioners may find it challenging to convey equipoise and explore treatment preferences. Materials and Methods Qualitative study embedded within ROAM/EORTC-1308. Data were collected on 40 patients and 18 practitioners from 13 U.K. sites, including audio recordings of 39 patients’ trial consultations, 23 patient interviews, and 18 practitioner interviews. Qualitative analysis drew on argumentation theory. Results Practitioners acknowledged the importance of the research question that the trial aimed to answer. However, they often demonstrated a lack of equipoise in consultations, particularly with eligible patients who practitioners believed to be susceptible to side effects (e.g., cognitive impairment) or inconvenienced by radiotherapy. Practitioners elicited but rarely explored patient treatment preferences, especially if a patient expressed an initial preference for active monitoring. Concerns about coercing patients, loss of practitioner agency, and time constraints influenced communication in ways that were loaded against trial participation. Conclusions We identified several challenges that practitioners face in conveying equipoise and exploring patient treatment preferences in oncology, and particularly neuro-oncology, trials with distinct management pathways. The findings informed communication about ROAM/EORTC-1308 and will be relevant to enhancing trial communication in future oncology trials. Qualitative studies embedded within trials can address difficulties with communication, thus improving informed consent and recruitment. ROAM/EORTC-1308 RCT: ISRCTN71502099.