A Restart CMA Evolution Strategy With Increasing Population Size Anne Auger and Nikolaus Hansen In this paper we introduce a restart-CMA-evolution strategy, where the population size is increased for each restart (IPOP). By increasing the population size the search characteristic becomes more global after each restart. The IPOP-CMA-ES is evaluated on the test suit of 25 functions designed for the special session on real-parameter optimization of CEC 2005. Its performance is compared to a local restart strategy with constant small population size. On unimodal functions the performance is similar. On multi-modal functions the local restart strategy significantly outperforms IPOP in 4 test cases whereas IPOP performs significantly better in 29 out of 60 tested cases. ERRATA: End of Section 2, stopping criterion "noeffectcoord": "Stop if adding 0.2-standard deviation in each coordinate does change ..." should be "Stop if adding 0.2-standard deviation in any coordinate does not change ..." The following has been pointed out by Xiao-Min Hu from the Sun Yat-sen University: 1) On function F4 the initial search point was chosen by mistake as Xup + (Xup-Xlow)*rand instead of Xlow + (Xup-Xlow)*rand The corrected initialization will presumably give better result. 2) On some function the boundary setting was omitted, but this has most probably no impact on the results.