SUMMARY This paper investigates the determinants of the performance of family farms in Senegal using both production and profit functions. The econometric analysis is based on agricultural inputs and outputs information from a survey of 504 agricultural households, member of a farmer organization in the Saint Louis region in 2009. Our main results indicate that the size of the cultivated plots has a negative effect on crop yields, representing diseconomies of scale. This finding suggests potential for improvements in farm management and organization. We also find that the development of commercialization sectors and loans could boost agricultural inputs. In terms of profitability, our results show that yields and prices play significant and important roles for all crops. An increase in the bargaining power of farmers would be required to increase unit prices and consequently their profits.