Aim. The aim of the presented study was an analysis and comparison of patients' and psychiatrists' beliefs regarding the most important aspects of bipolar disorder (BD) treatment. Method. A group of 100 psychiatrists (with at least 5 years' professional experience) and a group of 100 remitted patients fulfilling ICD-10 and DSM-IV-TR BD criteria (aged 18-65) were enrolled. Their beliefs were investigated with a 41-item structuralised questionnaire (doctors group) and 27-item self evaluation inventory (patients group). The structures of both tools made it possible to compare the results and were based on hierarchical ranking of answers included in each item. Results. A number of important concordances were indicated between doctors' and patients' beliefs, e.g. both groups considered that: 1/depression is the most burdensome episode in the course of BD; 2/pharmacotherapy is the most crucial element of treatment; 3/improvement in quality of life is the most important aspect of recovery. On the other hand, the results revealed that patients are convinced that doctors consider improving their life quality much less important than alleviating symptom severity. The hierarchy of problems proposed by the patients as the main obstacles in taking drugs appeared to be the exact antithesis of doctors' beliefs on this issue. The patients indicated the side effects of drugs as the main cause, whereas doctors considered compliance a crucial problem. Discrepancies in beliefs were also observed regarding the perceived importance of different psychoeducation topics: coping abilities and quality of life improvement - the two most important issues in patients' opinion were placed in a remote rank in the doctors' hierarchy, giving way to early recognition of relapse symptoms and suicidality prevention. Conclusion. Discrepancies in psychiatrists' and patients' beliefs regarding crucial aspects of BD treatment revealed in the study may be responsible for the worsening of quality of compliance.