Bipolar depression was diagnosed in the majority of patients attending psychiatric outpatients clinics in Poland in a survey recently published. Psychometric tools for assessment of depressive disorders currently used (i.e. the Hamilton Depression Scale or the Montgomery-Asberg Depression Rating Scale) were designed around the features of classic unipolar depression. A growing body of evidence suggests that there are phenomenological as well as psychopathological and pathogenetic differences between unipolar and bipolar depression. Hence, the principles of treatment of bipolar depression are distinct from the treatment algorithms for unipolar depression, and the metrics for symptom assessment need to reflect the unique phenomenological signature of bipolar depression. Here we present a newly elaborated scale for the assessment of symptoms of bipolar depression which has showed strong internal consistency, inter-rater reliability and correlations with other rating scales for depression. Additionally, Polish translation of the Bipolar Depression Rating Scale is enclosed.