Objectives: To explore the potential utility of clinical stage and mental disorder categories as a basis for determining which attributes of youth mental health care should be offered to which groups of young people. Methods: In June 2017, we conducted an online survey of youth mental health clinicians that collected information on the participants' background and areas of expertise, then presented vignettes describing young people with different stages of six mental disorders (disorder-based vignettes were matched to participants' area of expertise). For each vignette, participants were asked to give a quantitative estimate of the proportion of young people with similar mental health problems they thought would clinically benefit from each of twelve attributes of mental health care (other than pharmacological or individual psychological therapies). Survey results were analysed as independent, disorder-based samples, using standard statistical tests of significance, and as a stratified sample using mixed-effects models. Results: A total of 412 clinicians working in 32 countries participated in both parts of the survey. Respondents represented a broad range of clinical disciplines, settings and areas of expertise. Their estimated proportions of young people who would benefit from the mental health care attributes varied by clinical stage and disorder (eg, a mean of 93% [interquartile range (IQR), 90%–100%] of young people with Stage 2 psychosis were estimated to benefit from case management with a multidisciplinary team; while only 15% [IQR, 1%–25%] of young people with Stage 1b generalised anxiety disorder were estimated to benefit from collection and processing of biological samples). Neither the background of the respondents nor the sex of the characters in the vignettes significantly influenced the results. Conclusion: A combination of clinical stage and disorder information might be an appropriate basis for ensuring that the right attributes of early intervention mental health care are provided to the right young people at the right time. Policy and research priorities include trialling novel services, preferences research among young people, strengthening service responses to subthreshold disorders and promoting high-fidelity collection of clinical stage data in youth mental health settings.