BACKGROUND: Data from the Norwegian HUNT suggests that only 10-13% of individuals suffering from depression and anxiety have sought professional help, fuelling concerns that only a fraction of individuals with clinically significant mental health problems receive adequate treatment in Norway. AIM: The aim of this study was to examine formal help seeking for psychological distress in two communities in Norway (one urban and one rural) over time, in relation to the prevalence of distress. In addition, the proportion with potential unmet need for professional help was examined. METHODS: A randomly drawn selection of individuals from Oslo (urban) and Lofoten (rural), the OsLof study, were interviewed about help seeking and administered the Hopkins Symptom Checklist (HSCL-25) in 1990 and 2001. RESULTS: Results showed a significant shift in help seeking over time, whereas the prevalence of distress (HSCL-25 >or= 1.75) remained stable in both communities, ranging between 13% and 16%. A significant increase occurred in the proportion seeking help from psychiatrists/psychologists, together with a significant decrease in help seeking from GPs and non-medical services. CONCLUSION: Multiple explanatory factors might account for the decline in overall formal help seeking, such as the improvement in the economical situation observed across the decade. No urban-rural difference in help seeking was observed, despite Oslo having a higher calculated man-labour year in psychiatric services. Even though potential unmet need has been decreasing among the psychologically distressed, only 40% had sought help from mental health professionals in 2001, indicating the need of the speciality health services to address this issue further.