So far, the analysis was focused on wives' (bi-principalpotential earners') acceptance and rejection of emplpyment opportunityoffered by firms . There are, however , earning opportunity without beingemployed by the emplovers . As a matter. _ Of t other than employee ( self -employed . wives)are found in the FIES data, Hence, a comprehensive theory - originallybe able to treat the earning behavior of self-employed wives, too,From this point of view the theory of wives' (non principal potential)earners') labor supply behavior developed so far is of the firstapproximation in the sense that it describes wives' acceptanceor rejection of employee status Only. (I shall hereafter distinguish(--those two kinds of working wives (members) of households by----using phrases employee wives and self employed wives)We used the labor supply theory of first approximation of thiskind in order to estimate preference parameters . The results ofthe examination in section. (V )_seems to show that we need a moreprecise theory of labor supply, that is the theory of second . _approximation. As is mentioned above the second approximation theory should be able to clarify the behavior of self employedas well as employee wives . _In this context a more precise model of wives' labor supplyis developed in this section .