Complex phenotypes result from the interaction between genetic and environmental informations. Almost a decade ago, the discovery of acquired epigenetic inheritance has shown that individual’s environmental experiences can influence developmental and phenotypic trajectories across several generations. The field is now starting to unveil the molecular mechanisms, while its relevance for complex disease risk and adaptive evolution is still unclear and strongly debated. The aim of this chapter is to introduce the reader to the concept of epigenetic inheritance, provide an overview on the underlying molecular determinants and highlight its potential relevance for individual’s susceptibility to complex, non-mendelian, diseases.