to its furthest consequences. Two incidents in his life reveal the stringent requirements that he thought research imposed, and they show how demanding he was in his own work. While writing his Ph.D. thesis, he had gradually come to see that the neogrammarian framework in which he was working was out of date. That made him categorically refuse to publish his thesis, in spite of its excellence. The 1956 publication of his habilitation, highly specialised as it was, sold out fairly quickly, and the KNAW had it reprinted, unchanged and published in 1964 without his knowledge. When he eventually found out, he demanded and obtained all copies that were still unsold to be called back and for a notice to be inserted to the effect that he would have wanted to modify certain parts, in view of recent research. He could get very upset at researchers whose work was not careful or who used it as a means of self-promotion. However, he deeply appreciated and respected serious researchers, whatever their orientation or philosophy. The history of Toward a Grammar of Proto-Germanic is revealing in that respect. He had planned the work as a modern successor to Eduard Prokosch's 1939 A Comparative Germanic Grammar, and he had brought together a number of distinguished historical linguists for the purpose. However, the chapters that they contributed were very diverse in nature (some were suitable for a textbook, others contributed original and advanced research) and in approach (some were clearly structuralist, others worked within generative linguistics). Coetsem respected his authors and published their contributions as they were, rather than imposing a format or an approach, though that forced the original plan to be abandoned. The book was a series of contributions Toward a Grammar of Proto-Germanic, rather than a grammar of Proto-Germanic proper. Coetsem's research ranged wide, and his knowledge of general linguistics was vast. His own research can usefully be assigned to four subfields of linguistics. His first research (his Ph.D. and his work at the WNT) was on Dutch, and he would work on Dutch throughout his career, focusing often on variation within Dutch: between the Netherlands and Flanders, his 1957 article on the national border between the Netherlands and Flanders as a language border, brief as it was, being cited extensively, and between the dialects and the standard language. He was also the linguistic expert behind a highly popular language program