An established stylized fact of OECD countries is trendless unemployment over the long run (e.g. over the last century). The present paper derives conditions for trendless unemployment in a model with endogenous technical progress. The results are consistent with earlier findings in a model with exogenous technical progress, but are in sharp contrast to the thesis in Karanassou, M. and Snower, D., 2004. Unemployment invariance. German Economic Review, 5(3), pp. 297-317, in a reduced form model with endogenous technical progress.