GWAS have brought many successes to detect DNA-variants for common diseases and other traits. Feasibility to genotype a large amount of SNPs cost efficiently in big populations with various study designs benefits GWAS in contrast to candidate gene studies. However, they only explain a small proportion of estimated heritability so far. It’s still a long way to go, to develop methods to discover false negative signals, find other impact e. g. from epigenetics or gene-environment interaction as well as to translate all findings into better understanding of disease and clinical practice.