Summary The paper exploits large-scale administrative data to analyse trends in male earnings inequality in Luxembourg during 20 years of rapid economic growth, industrial redevelopment and massive inflow of foreign workers. A detailed error components model is estimated to identify persistent and transitory components of (the trends of) log-earnings variance and to disentangle the contributions to it of native, immigrant and cross-border workers. The model is flexible and allows for a high degree of individual, age, time and cohort heterogeneity. We observe a surprising stability in overall earnings inequality as a result of more complex underlying changes, with marked increases in persistent inequality (except among natives), a growing contribution of foreigners and a decrease in earnings instability (primarily for natives).