The profile of allergic disease worldwide continues to change as the number of severe IgE-mediated allergies increases. This phenomenon is thought to reflect the outcome of combined genetic/environmental/developmental/stochastic effects on immune development, but understanding this remains a challenge. Epigenetic disruption at key immune genes during development has been proposed as a potential explanation for how environmental exposures may alter immune cell development and function. This represents an emerging area of research with the potential to yield new understanding of how disease risk is modified. Here, we examine recent developments in this field that are defining new epigenetic paradigms of allergic disease.