This manuscript is part of a special issue to commemorate professor Paul Eelen, who passed away on August 21, 2016. Paul was a clinically oriented scientist, for whom learning principles (Pavlovian or operant) were more than salivary responses and lever presses. His expertise in learning psychology and his enthusiasm to translate this knowledge to clinical practice inspired many inside and outside academia. Several of his original writings were in the Dutch language. Instead of editing a special issue with contributions of colleagues and friends, we decided to translate a selection of his manuscripts to English to allow wide access to his original insights and opinions. Even though the manuscripts were written more than two decades ago, their content is surprisingly contemporary. The present manuscript was originally published as part of a Liber Amicorum for Paul Eelen's own supervisor, prof. Joseph Nuttin. In this chapter, Paul Eelen presents a modern view on Pavlovian learning. It appeared in 1980, at the heyday of cognitive psychology which initially dismissed conditioning. Paul Eelen's perseverance in presenting learning principles as key to study human behaviour has proven correct and ahead of time. First published as: Eelen, P. (1980). Klassieke conditionering: Klassiek en toch modern. In Liber Amicorum, Prof. J. R. Nuttin, Gedrag, dynamische relatie en betekeniswereld (pp. 321-343). Leuven: Universitaire Pers Leuven.