Rare earth chemistry has witnessed remarkable advances in recent years. In particular, ancillary ligands other than cyclopentadienyl derivatives have been introduced to the organometallic chemistry, and their complexes exhibit distinct reactivity and properties compared to the metallocene or half-sandwiched analogs. This chapter reviews arene-bridged rare earth complexes with an emphasis on those compounds obtained by reduction reactions. A particular emphasis is placed on rare earth complexes supported by 1,1'-ferrocenediyl diamides since they show the most diverse chemistry with arenes: Fused arenes, such as naphthalene and anthracene, formed inverse-sandwiched complexes, in which the arene is dianionic; weakly conjugated arenes, such as biphenyl, p-terphenyl, and 1,3,5-triphenylbenzene, were unexpectedly reduced by four electrons and led to 6-carbon, 10π-electron aromatic systems; on the contrary, (E)-stilbene, which has a carbon-carbon double bond between the two phenyl rings, could only be reduced by two electrons, which were located on the carbon-carbon double bond instead of the phenyl rings. The reactivity of some rare earth arene-bridged complexes is also discussed with noticeable examples being the activation of white phosphorus (P4) by rare earth naphthalene complexes. Stoichiometric P4activation led to polyphosphide (P84-P84-or P73-P73-), which could then be transferred to phosphorus-containing organic molecules. © 2014 Elsevier B.V.