Introduction: As little is known about who uses specialty mental health clinics for persons with intellectual disabilities, this study aimed to identified caregiver concerns, clinical characteristics, and the relationship between these two constructs for referrals to such a clinic. Methods: Qualitative and quantitative analyses were applied to data derived from an intake questionnaire of all individuals referred to a specialty clinic in Canada over one year. Results: The dataset consisted of 149 persons (55.7% male; 37.6% with autism; mean age: 28.8 years [SD: 13.2]). The two overarching categories of caregiver concerns were about: (1) aspects of clinic service, especially medication questions; and (2) specific emotional, behavioral, and diagnostic concerns, especially regarding emotional states. Caregivers of persons with autism had higher odds of medication concerns, but few other significant relationships were found. Conclusions: Further investigations about emotional difficulties and medication concerns, inclusive of perspectives of persons with intellectual disabilities, are needed.