Although technological progress is driven by technological learning derived from domestic and foreign knowledge sources, the dynamic interaction between the two principal learning modes—learning by doing (domestic sources) and learning by importing (foreign sources)—remains insufficiently understood, despite their crucial influence on a country’s transition from duplicative imitation to creative imitation and eventually to innovation. Drawing on an embedded case study of China’s successful catch‑up in nuclear power reactor technology, we identify a “smile curve” in the evolution of technological learning, wherein the relative significance of learning by doing and learning by importing follows a U-shaped trajectory. Furthermore it shows that intangible (e.g., talent acquisition) and tangible (e.g., equipment) components of learning by importing exhibit the same smile curve pattern. These findings provide potential solutions for latecomers to overcome technological catch-up challenges through sequence learning strategies.
