Background: The aim of this study was to explore clinician perspectives on patient decision-making in multidisciplinary care for amyotrophic lateral sclerosis (ALS), in an attempt to identify factors influencing decision-making. Methods: Thirty-two health professionals from two specialized multidisciplinary ALS clinics participated in individual and group interviews. Participants came from allied health, medical, and nursing backgrounds. Interviews were audio recorded, and the transcripts were analyzed thematically. Results: Respondents identified barriers and facilitators to optimal timing and quality of decision-making. Barriers related to the patient and the health system. Patient barriers included difficulties accepting the diagnosis, information sources, and the patient-carer relationship. System barriers were timing of diagnosis and symptom management services, access to ALS-specific resources, and interprofessional communication. Facilitators were teamwork approaches, supported by effective communication and evidence-based information. Conclusion: Patient-centered and collaborative decision-making is influenced by a range of factors that inhibit the delivery of optimal care. Decision-making relies on a fine balance between timing of information and service provision, and the readiness of patients to receive them. Health system restrictions impacted on optimal timing, and patients coming to terms with their condition. Clinicians valued proactive decision-making to prepare patients and families for inevitable change. The findings indicate disparity between patient choices and clinician perceptions of evidence, knowledge, and experience. To improve multidisciplinary ALS practice, and ultimately patient care, further work is required to bridge this gap in perspectives.