This book deals with the notion of reformulation and more specifically with a group of lexico-grammatical units which help codify and signal the activity of reformulation in English. While discourse markers in English have been described in detail, the area of reformulation is a relatively unexplored area in comparison with languages such as French or Spanish. In this respect, this book has been conceived as a contribution to the field of Discourse Markers and in particular to the markers that help display the function of reformulation in English. First of all, a definition of the notion of reformulation is provided as a necessary precondition for the elaboration of a taxonomy of English reformulators. These are grouped into different classes and sub-classes on the basis of the type of reformulation effected. Thus, four main types are identified: Expansion, Modification, Reassessment and Compression. After an inductive and interpretive analysis of examples taken from the British National Corpus (BNC), the syntactic and distributional properties of these units, as well as their environments of use are described and discussed.