In this chapter, we review central criteria that are commonly used to differentiate between ‘(total) reduplication’, understood as a grammatical operation that applies within word boundaries, and ‘(exact) repetition’, which is a pragmatic or discourse-related process that takes place above the word level. The main focus of this article is on the grey area where the two domains meet or even overlap. In anticipation of the remainder of the book we discuss examples from a variety of languages which challenge a neat division into word-bound reduplication on the one hand and discourse-bound repetition on the other. This survey of potentially problematic cases leads to the conclusion that the demarcation line between reduplication and repetition is rather blurred: Neither is reduplication confined to the domain of the word nor is repetition completely excluded from it. Reduplication also occurs at the discourse level, conveying discourse-grammatical information such as topic marking. Conversely, purely pragmatically motivated processes of repetition can also be found within words, for example with derivational affixes and in ideophones. This introductory chapter is concluded by an overview of the articles assembled in this book.