This pilot study tested the use of a best-worst scaling (BWS) instrument to aid caregivers of a child with mental health comorbidities in clarifying preferences for treatment outcomes. BWS methodology closely approximates real-life decision-making by requiring the selection of one “most important” and one “least important” among a group of competing attributes. 38 caregivers were recruited from support groups in Maryland from March through July of 2015. Criteria for participation were a) their child was 21 years or younger, b) was diagnosed with a developmental delay related to cognitive or emotional disability and, c) with a comorbid mental illness (i.e. ADHD, depression, anxiety, etc.). Subsequent to survey completion, the caregivers took part in one of 6 debriefing sessions to determine the ease of comprehension, relevance of the concepts, distinctiveness of the statements, and clarity of language. The dataset includes family demographics, child characteristics (diagnoses, type of treatment, etc.), session transcripts, and statistics associated with the caregiver responses to the attributes included in the BWS instrument.