The study of the identity processes of women of color in science-based fields helps us (a) find ways to support similar women, and (b) study the dynamics of inequity, within and beyond science. Participants in this study (a Black woman, a Latina, and an American Indian woman) survived inadequate high schools and discouraging college science departments to win formal recognition (fellowships, publications). Using multiracial feminist theory, including intersectionality, and practice theory, we conceptualize authoring of identity as an ongoing process. Qualitative methods were designed around Black feminist precepts of caring and personal accountability, the use of concrete experience and of dialogue (Collins, 2000a). Participants' opportunities to author legitimate science identities were constrained by their location in the matrix of oppression. They reported conflicts between their identities as women of color and as credible science students, and having racist, sexist identities ascribed to them. All became more adept at fending off negative ascription and all found settings with less identity conflict; their ability to read a situation and quickly adjust, "la facultad" (Anzaldua, 1999) helped them survive. But the fact that they have needed to do this is unjust. (Contains 2 tables and 9 notes.)