To reduce stigma and improve help seeking by young people for mental illness, we need a better understanding of the associations between various dimensions of stigma and young people s help-seeking intentions and helpfulness beliefs for various sources of help and for different disorders. This study assessed stigmatizing attitudes and help-seeking intentions and helpfulness beliefs via a national telephone survey of 3021 youths aged 15-25. Five stigma scales were used: social distance, personally held weak-not-sick and dangerousness beliefs, and weak-not-sick and dangerousness beliefs perceived in others. Respondents were presented with a vignette of a young person portraying depression, depression with suicidal thoughts, depression with alcohol abuse, post-traumatic stress disorder, social phobia, or psychosis. Beliefs that mental illness is a sign of personal weakness and preference for social distance were associated with less intention to seek professional help and less endorsement of their helpfulness. In contrast, dangerousness/unpredictability beliefs were associated with more intention to seek professional help and more endorsement of their helpfulness. Findings highlight the importance of examining the associations between different dimensions of stigma with different sources of help, specifically for various mental disorders, to better inform future efforts to reduce stigma and increase help seeking in young people.