Between 1628/20) and 1641, in Rome, the painter, draughtsman and etcher Herman van Swanevelt (ca. 1600-1663) developed, in collaboration with Claude Lorrain (who was the same age as himself), a genre that was to have far-reaching consequences: the idyllic, ideal landscape characterised by effects of light appropriate to the time of day. His most eminent patrons during this period were the Barberini and Philip IV of Spain. In his Paris years, from 1643/44, he catered to another circle of customers with perfect but less innovative paintings and most of his highly successful sets of etchings. Up to Goethe's day, and notably in France, renderings of the landscape influenced the development of the period's taste. Anticipating a monograph in progress with a critical oeuvre catalogue of Swanevelt's drawings and paintings, this article presents fourteen drawings for frescos and paintings dating from 1634 to after 1650. These drawings form a record of Swanevelt's stylistic development throughout virtually his entire working life. Research has already linked six of them with frescos and paintings; they are presented here with further-reaching pointers. Six of the other eight drawings are examined in detail, two more briefly in view of the impending publication of an article. The discussion centres on the function of the drawings (preliminary / copy / variant / ricordo / autonomous) and their chronology. The article is preceded by a brief biography of the painter, summarising the scattered published results of relevant research. There are two appendices: the first is a list of dated drawings (15); the second lists the dated paintings (43).