Rice-maize system is a newly emerging cropping system, which covers about 336000 ha in India. The system is basically initiated by the farmers as an option to diversify of the classical rice-rice and rice-wheat system. This change is not only due to necessity to cope with the problems in the classical systems but also some opportunity in terms of intensification and increased net return over the classical system. During the 1970s, input responsive high-yielding cultivars of wheat and rice were introduced and adopted on large scale. Being a high-input demanding/utilizing system, however, some weaknesses of these cropping systems were prevalent by the mid 1990s. This includes restricted moisture availability for the second crop (wheat or rice), declining ground water tables, decreasing factor productivity, input use efficiency and net returns, herbicide resistance in some biotypes of weeds and increasing biotic pressure due to monoculture. These emerged as potential constraints for the farmers and forced them to look for other alternative crop sequences, including rice-maize. Apart from the necessity, farmers also realized some opportunities with rice-maize, including – intensification of the system to make it more profitable, utilization of Tal areas by growing winter maize only on residual moisture, harvesting high yield potential of maize during winter, growing maize as cash crop after rice to meet its increasing industrial demand, removing the herbicide resistant weed biotype etc. Several benefits have already been realized with this shift; however, there are issues that need to be addressed to make the system more feasible and profitable. Scientific interventions are urgently needed towards identification/development of suitable cultivars for this new system, improving early stage excessive moisture, low temperature tolerance and terminal drought/heat tolerance in maize, improving tolerance to various soil-born diseases caused by high moisture and humidity loving organisms, and nutrient dynamics and management in rice-maize system.