Grasspea (Lathyrus sativus L.) is a versatile cool-season legume that is commonly used as food and fodder. It is a hardy legume that is adaptable to varied fragile agroecosystems as it can tolerate drought, salinity, and flood and has multiple uses in the pharmaceutical and industrial sectors apart from its use as food. It is a rich source of protein, folic acid, and minerals and the only dietary source of L-homoarginine. The cultivation of this crop was undermined because of the presence of β-ODAP in its seed, which may cause neurotoxic effects when it is consumed as a sole diet for longer periods. The development of improved varieties with earliness, high biomass, and low ODAP content are the pipeline breeding objectives in this underutilized legume. This chapter deals with the importance of this crop, its wild relatives, cytogenetics, breeding programs, and future perspectives.