Equipped with an essential understanding of ADRC, one could confidently move to the second part of the book, which deals with its practical implementation. But for those wishing to get a wider look at the topic of ADRC and get a bit more context than what has been provided in the book so far, we use this chapter to take a quick pause and look around. Here we recall what we covered so far in the first part, put things in historical perspective, and provide relevant bibliographical support. We also briefly touch on some of the topics in the area of ADRC, which, although interesting and horizon-broadening, go beyond the scope of this book, which is focused on fundamentals. Finally, we discuss what is to come in Part II.