Art history has not given Adriaen Thomasz Key's legacy its proper due, to say the least. After a short and successful artistic career in a turbulent period, Adriaen Thomasz Key vanished from the stage for centuries. Barring his art, he left few other traces behind and over time even this came to be riddled with the most far-fetched attributions. In the past, connoisseurs were often at a complete loss. Adriaen Thomasz's pictures were ascribed to a host of painters from numerous countries and periods. The names of Frans Pourbus the Elder and Willem Key, for instance, were linked to several of Adriaen Thomasz's panels. Other works had to endure attributions which had nothing in common with the quality, let alone the art, of the master. Dozens of inferior portraits were given to Adriaen Thomasz and many of his altarpieces and devotional scenes were not recognised as such because he was considered solely as a portraitist. Consequently, up until now the image of Adriaen Thomasz's art has been clouded and inconsistent. Adriaen Thomasz Key richly deserved his reputation as a portraitist. Some ninety percent of his preserved oeuvre consists of likenesses of the Antwerp and the Dutch elite. Adriaen Thomasz's skills as a portraitist were and are generally acknowledged. With a finesse and sobriety recalling that of Flemish Primitives such as Jan van Eyck and Hans Memling, he recorded his sitters with ruthless objectivity. The same sobriety and objectivity are to be found in his altarpieces and devotional paintings, a less known facet of his art. Often incorrectly ascribed as a lack of ingenuity or understanding of the Italian Renaissance and typified as archaising, Key's history and devotional paintings prove to be of a huge intellectual resourcefulness and artistic talent. His art was a conscious, reformatory and humanistic intellectual discourse with his famous predecessors and contemporaries. The striving for photographic realism and sobrietyin the oeuvre of the painter is tackled in this monograph, bearing in mind Adriaen Thomasz's humanistic concerns with iconography. This richly illustrated monograph brings to light, for the first time, the oeuvre of a painter, called the most talented of his generation by David Freedberg. It consists of portraits and altarpieces, devotional paintings and chiaroscuro prints. The rediscovery of Adriaen Thomasz Key's art will be a eye opener to all scholars interested in the Netherlandish Renaissance and will hopefully induce new research into Adriaen Thomasz Key and his contemporaries.