The late-Renaissance keyboard music of Jan Pieterszoon Sweelinck is virtuosic to a high degree, reflecting both his exceptional skills as an improviser and the secular role organ music was assigned in Reformed Amsterdam. Without a liturgical function to constrain his imagination or shape his music – Calvinist services had no place for it – Sweelinck was free to provide fanciful showpieces for his daily recitals in the Oude Kerk. Examples of his improvisational style can be found in the quasi-fugal Hexachord Fantasia, the witty Echo Fantasia, and the flamboyant Toccatas, of which three are included here. Yet Sweelinck's music is also rigorously logical and full of ingenious contrapuntal devices. These are readily found in his fantasias, but are prominently featured in his numerous sets of variations. His elaborate settings of the chorales Allein Gott in der Höh sei Ehr and Erbarm dich mein, o Herre Gott, and his variations on popular melodies, such as the famous Mein junges Leben hat ein End, display his invention and thorough manipulation of his subjects in all registers. Perhaps better known as a harpsichordist, Robert Woolley is also a fine organist. Woolley has selected representative works from each of Sweelinck's favored genres and given them exceptional performances on the Van Hagerbeer organ of the Pieterskerk, Leiden.