In Norwegian research universities, a large individual increase has taken place in scientific and scholarly publishing over the last 30 years. The purpose of this article is to explain the reasons for this growth in a generational perspective. We put forward six hypotheses that can be illuminated by cross-sectional data drawn from five surveys to academic staff and by data from other statistical data sources. New generations of academic staff: (a) are better qualified, (b) have better publication opportunities, (c) have better funding and research conditions, (d) use more time for research, (e) collaborate more in research and (f) are affected by the introduction of incentive and reward systems conducive to scientific publishing. Four of these hypotheses are supported by our data as partial explanations of the increase in productivity: Better qualified new generations of academic staff, the increase in research collaboration, improved funding and research conditions and the introduction of incentive systems. In addition, a general change in norms for appropriate academic behaviour contributes to explaining the productivity increase.