Text in German and English. Stefan Heiliger is one of the most prominent product designers in Europe, known for his -- often mechanically assisted -- recliners, easy chairs and couches. He has designed strategic ergonomic, social and comfort transitions between 'sitting-lying' and 'lying-sitting' more than almost any other designer. In his work diverse influences come together: first, familial heritage, his father Bernhard Heiliger's sculptural sensibilities; second, experiences gained during his studies at the famous Ulm School of Design, and during his time with Wilhelm Wagenfeld; and, last but not least, professional experience as a designer for Daimler-Benz in Stuttgart. The formal vocabularies that Heiliger uses in his recliners, easy chairs and couches have an inner relationship with his sports-car and coupé designs. The saucy radii, parables, hyperbolas and circular segments, the rhomboids, tetrahedrons and bevelled ovals witness a trust in the emotional, even erotic power of curvatures that may stem from automobile design. Also, the metaphors of frozen speed, which invariably characterise Heiliger's functional chairs, justify the term 'boldismo'. It seems evident that Heiliger is as much an emotional functionalist as he is a sculpturally thinking pragmatist. Heiliger, who has also passed down his talent and experience to students as a design professor for almost three decades, has compiled a decidedly contemporary vocabulary with new forms of spectacular body shells for the subject area 'comfort seating'. Today, he provides interior design products for the biomorphic 'blob architecture' in a congenial way without any fixation on axial orientations or rectangularities. The present publication document and interprets Stefan Heiliger's uvre and places it into a historical design context.