Since it was first defined by Christopher Wild, to today, the concept of the exposome has evolved into a valuable tool to evaluate human exposure and health. In the chapters of this book the definition of the exposome paradigm and concept is discussed. The most recent techniques based on OMICs, targeted and untargeted analysis for its characterization are described. The challenges arising from the amount of data that needs to be processed to understand the complex mechanism behind exposure and health outcome, as well as the latest statistical and data analysis methods have been discussed. Finally, multiple projects across the globe have or are currently tackling the application of the exposome concept to real studies, and these studies have been presented in this book. In this section, we will provide a chapter summary, and describe how the exposome paradigm has advanced since its definition. We will also explore question such as: what have we learned so far? Does the exposome paradigm provide valuable information? And what needs to be improved? Finally, we will discuss the possibility of future applications of the exposome in disease causality and personalized medicine.