With this collection of short review papers we would like to present a broad overview of research on poly?uorenes and related heteroanalogues over the last two decades. The collection begins with papers on the synthesis of po- ?uorenesandrelatedpolyheteroarenes, thenreportsphotophysicalproperties of this class of conjugated polymers both at the ensemble and the single chain level, continues with a discussion of the rich solid state structures of poly?uorenes, and ?nally switches to device applications (e.g. in OLEDs). In addition, two chapters are devoted to de?ned oligo?uorenesas lowmolecular weight model systems forpoly?uorenes and also to degradation studies. We feel that this up-to-date collection will be very helpful to all polymer chemists and physicists, and will also aid graduate students interested in this fascinating and still growing area of research, since such a compact overview is only now available. All articles are presented by leading scientists in their ?elds, insuring state-of-the-art coverage of all relevant aspects. Together with the body of references this volume is meant to assist researchers in the daily lab routine. Moreover, Advances in Polymer Science, as an established series of high quality review papers, represents a very appropriate platform for our project.Wehopethatthisshortcollectionwillbeofgreatvaluebothforbeg- ners and established researchscientists inthe?eldofpoly?uorene research.