The present study was conducted to ascertain the yield gaps and constraints in the production of jowar, groundnut arid cotton in north Kamataka. Primary data from 240 sample farmers and secondary data from concerned research station were collected for the agricultural year 1996-97. Tabular, Cobb-Douglas and Frontier production function, Path and Decomposition Analyses were used for the analysis of data. The index of yield gap worked out to be 58.83 per cent, 57.43 per cent and 56.55 per cent for jowar, groundnut and cotton, respectively. Nearly 70 per cent of potential farm yield in jowar and groundnut and 65 per cent of the potential farm yield in cotton was realised by the sample farmers. The significance of the dummy (technique of production) coefficients confirmed the structural difference in the production surfaces between the demonstration plots and the farmers field. Path analysis revealed that input gaps have a high degree of association with the yield gaps. Plant nutrient excerted the maximum direct effect on the observed yield gap in jowar and groundnut, whereas, it was human labour in cotton. Decomposition analysis also showed that difference in cultural practices between farmers field and demonstration plots was the major contributing factor to the yield gap in jowar (21.42%) and cotton (27.79%), while input gap contributed for the highest share in groundnut (18.58%). Among the various inputs, plant nutrient (jowar and groundnut) and human labour (cotton) accounted for the major portion of the yield gaps. In the study area jowar sample fanners achieved about 70 percent frontier output, whereas, slightly greater (80%) efficiency was recorded by groundnut and cotton sample farmers. The Kopp measure of allocative efficiency analysis showed a very high degree of inefficiency in the use of resources for all the three crops. The resource use efficiency analysis revealed that profitability ratio, for most of the crops differed from unity. Thus there is a need for reallocation of expenditure among different resources so as to optimise the crop production.