Delayed nodule senescence may improve nitrogen content in the legume seed and increase the yield of production. This review focuses on using the strategy of modulating ACC deaminase enzyme levels as an indirect way to delay nodule senescence. Nodule senescence occurs by developmental or aging processes, and by stress-induced nodule senescence. Both processes share several characteristics, including the decline in N2 fixation, leghemoglobin, and antioxidant enzyme levels, as well as the oxidative damage of cell components caused by induction of ethylene production inside the cell as a signal to activate other systems involved in the acceleration of nodule senescence. ACC deaminase-containing rhizobia can degrade ACC, a precursor of the ethylene biosynthesis pathway, leading to a reduction of ethylene production inside the cell and indirectly to a delay in nodule senescence. Details of nodule senescence processes and signaling, as well as the role of ACC deaminase in legume-rhizobia nodulation and delay of nodule senescence, are discussed in this review. © 2015 by John Wiley & Sons, Inc. All rights reserved.