The eminent palaeontologist and Greenland explorer Claus Heinberg was born in 1945 and died in 2021 after prolonged illness. His scientific production was focused on two remarkably different subjects: the bivalve fauna of the Cretaceous- Palaeogene (K-T)boundary beds and the Mesozoic geology and stratigraphy of eastern North Greenland. He was employed at Roskilde University during most of his career until he retired in 2012. He was part of a cross disciplinary collaborative environment, comprising biologists, geographers, geologists, sociologists, civil engineers and architects. He was a highly engaged social debater of a wide spectrum of societal subjects throughout his life. He was a fine person, a good colleague and friend.