The Danish linguist Viggo Brøndal (1887-1942) was a romance language and literature professor at the University of Copenhagen. He was a co-founder, with Louis Hjelmslev, of the Copenhagen Linguistic Circle in 1931 but died early. The two of them developed very different branches of structuralism. Hjelmslev’s version was stark, attempting to avoid metaphysical commitments, while Brøndal was influenced, among other things, by logic, epistemology, and phenomenology. He outlines his leading structuralist theory in Ordklasserne (Word Classes, 1928), later publishing books such as Præpositionernes Theori (A Theory of Prepositions, 1942). The posthumous Essais de linguistique générale, 1943, also includes contributions in English and French. He was more semantically oriented than Hjelmslev and contributed, in semiotics, to Greimas’ theory with his notions of neutral and complex relations. He distinguishes, most importantly, between types of relations, and forms of relations. Basic types are the four: Descript, descriptor, relator, andRelate – D, d, r, and R – that is, object of description, the act of describing, the act of relating, and the object of relations. The combination of those he argued gave rise to more complex structural semantic units, e.g. in word classes. This paper gives an intro to his work as seen from semiotics.