All Herbert's dramas originated relatively early. The first four dramas were written between the years 1956 and 1961, and only the last one, the monodrama "Listy naszych czytelników" ("Letters from Our Readers"), in 1972. Some of these works were created as radio plays, or later, adapted for radio. We can observe this in their structure as tension is produced mainly by means of sound (main characters' voices, sounds in the background, or silence); some other theatrical measures appear to a minimum degree. Even the poet used the term "drama for voices".