This qualitative study examines the writing and writing experiences of six bilingual (Spanish-English), immigrant university students. Immigrant students are a growing segment of university populations, but explicit/implicit language policies often overlook their unique characteristics and needs. The study draws on the continua of biliteracy model (Hornberger, 1989; Hornberger & Sklton-Sylvester, 2000) as well as concepts of language as dialogic (Bakhtin, 1986) to understand and theorize students' writing and writing experiences. It uses a constructivist paradigm (Mertens, 1998), combining narrative inquiry (Clandinin & Connelly, 2000) with aspects of grounded theory (Strauss & Corbin, 1998). Data sources included 40 hours of interviews (18 literacy history and 12 text-based interviews), more than 100 pages of student writing (from high school, university freshman composition courses, courses from students' majors, scholarship essays, creative writing, and Spanish writing), and documents including syllabi and assignment sheets. Following Ivanic's framework, data analysis centered on the participants' "autobiographical selves" (1998), with a focus on literacy histories, writing and writing experiences in the university, and the students' understandings of themselves. A constellation of factors in the students' literacy histories informed their experiences with language and literacy: subtractive and additive educational environments, age of arrival to the United States, education in the home language, quality of high school experiences, and socioeconomic status. The concept of mediated agency (Wertsch, Tulviste & Hagstrom, 1993) was used to conceptualize students' acts of "going against the grain" or accommodating the university context in their writing. The university context was often seen as challenging for some of the students, but some contexts, Latina/Latino Studies courses and an African-American Studies course, were particularly inviting for three of the six participants. In such inviting contexts, the participants experimented more with expressing their cultural identities, or with using Spanish in their writing. The majority of the participants drew on rich social support networks as they engaged in academic writing, and chose not to utilize the university writing center. The participants connected to writing politically (by referencing the Latino community and activism), safely (by avoiding sharing certain aspects of their identities, choosing neutral topics, and topics that met perceived expectations), and personally (by referencing personal experiences and stories). The participants developed stances toward writing that grew out of their literacy histories by: (a) seeking healing, (b) taking risks, and (c) overcoming obstacles. The participants showed ways in which their experiences developing as writers continued in the university. The participants' writing developed in that they: (a) asserted identities in writing, (b) took risks to express previously withheld aspects of their identities, and (c) negotiated how to relate their identities to the university context. Major implications of the study focus on the importance of understanding the complexity of immigrant students' experiences and the nuances of bilingualism. Maintenance of the first language is important from a young age and may have lasting effects into college. Home literacy instruction in the first language may play a role in downplaying the negative effects of a subtractive environment at school. Furthermore, students' home languages can be a resource that they draw on in the university as they develop their academic writing in English. Immigrant students who have experienced racism and linguistic chauvinism can benefit from explicitly safe spaces to explore these issues and it may help them develop as writers. It is important to learn more about students' use of social networks and build them into university support services. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]