The critic F. S. Boas adapted the term to characterise certain plays by Shakespeare that he considered to have characteristics similar to Ibsen's 19th-century problem plays. Boas's term caught on, and Measure for Measure, The Merchant of Venice, Timon of Athens, Troilus and Cressida, and All's Well That Ends Well are still referred to as "Shakespeare's problem plays". As a result, the term is used more broadly and retrospectively to describe pre-19th-century, tragicomic dramas that do not fit easily into the classical generic distinction between comedy and tragedy.
The most important exponent of the problem play, however, was the Norwegian writer Henrik Ibsen, whose work combined penetrating characterisation with emphasis on topical social issues, usually concentrated on the moral dilemmas of a central character. In a series of plays Ibsen addressed a range of problems, most notably the restriction of women's lives in A Doll's House (1879), sexually-transmitted disease in Ghosts (1882) and provincial greed in An Enemy of the People (1882). Ibsen's dramas proved immensely influential, spawning variants of the problem play in works by George Bernard Shaw and other later dramatists.