This paper explores the specialisation of European Union (EU) regions in key enabling technologies (KETs) and assesses whether or not being specialised in these technological areas has an effect on regional growth. The evidence presented shows that regions specialised in KETs are concentrated in central Europe; however, over the period taken into account (1996–2011), less innovative and peripheral EU regions have been increasing their specialisation in these technological areas at the expense of the most advanced regions. There is also evidence that (spatial) diffusion of KETs often occurs across regions contiguous to each other. The results of the econometric estimations show that being specialised in KETs affects regional economic growth (per capita gross domestic product) and that this effect is stronger in the case of less innovative EU regions. Overall, these results hint at the pervasive nature and enabling role of KETs and demonstrate the importance for EU regions to target these technologies as part of their smart specialisation strategies.