Transition metal and main group compounds bearing η 1 -indenyl ligands have figured importantly since the beginnings of organometallic chemistry, and continue to attract considerable attention. The novel reactivity of the transition metal derivatives and the utility of the main group species as ligands in the development of chiral metallocene pre-catalysts have led to a renaissance in this field of study. The dynamic behavior of these η 1 -indenyl complexes has also been examined: the preponderance of evidence points to a circumambulatory process involving sequential [1,5]-elementotropic shifts that proceed via short-lived isoindene intermediates.