Several economic models were fitted in this work referring to income determination of families seated in projects of Cédula da Terra Program. The estimates are obtained from a two-stage cluster sample and the models were fitted considering demographic, social and economic variables and referring to sub-samples of federation units and strata of projects size. The main conclusions reaffirm that the program beneficiaries' income is multi-determined for a wide set of factors, between which have relevance the education (in spite of being low), the work effort, the work opportunities out of the lot, the area of the lot and the level of social organization of the producers. Through the fittings of the models for each federation unit were verified the occurrences of specific factors, each being confronted with the researchers' direct observation. The results also indicate that the projects of medium number of families (20 to 38 families) are the ones that possess more potential use of its collective organization capacities in the associative work.