While self-disclosure is an important feature of adolescent peer friendships there is little evidence to identify how disclosure processes are affected by the online environment. A qualitative analysis of two online groups, established for research purposes, enabled a comparison of disclosure processes in young people with chronic skin conditions. Young people with psoriasis took part in a series of real-time discussions, while counterparts with vitiligo communicated through a non-real-time message board. The groups were observed and content analysis was used to identify the forms of support exchanged. Both groups used disclosure to elicit and provide support although interaction styles varied between the groups. Factors including rapport and anonymity are identified as influential in this mediation of social support. The findings are compared to a model of self-disclosure in online support groups (Tichon and Shapiro, 2003) and implications for online interventions with young people are considered.