Evolutionary structural optimization (ESO) constitutes a method of topology optimization which was pioneered by Y.M. Xie and G.P. Steven. The underlying principle is simple: One starts from a given volume made up from structural elements on predefined supports and with preset loads acting on it. Calculating the structural response will show that there are regions which carry more of the external load than others. Now one removes a number of those elements of the structure that are least strained and thus least effective. Again the response of the now thinned out model is determined, under-utilized elements removed and so on. This iterative procedure stops when a target volume or number of remaining structural elements is reached.