This article describes an adolescent's development of multiliterate and multilingual writing practices and identities. It further explores how a literacy teacher enacted a writing pedagogy of multiliteracies that assisted the youth in building writing practices and identities. Data include interviews of the young woman and her teacher, classroom observations, and literacy artifacts produced and used by the adolescent. These data are analyzed using theories of identity, positioning, communities of practice, and multiliteracies. Findings include that the youth developed her writing practices and identities over time and across multiple contexts of multiliterate and multilingual practices. Within and across these communities, the dimensions of apprenticeship, positioning, and recruitment of multiliterate and multilingual repertoires were essential to the youth's development of writing practices and identities. These dimensions were also central to the literacy teacher's enactment of a writing pedagogy of multiliteracies. The article asserts that attending to the processes through which young people develop their multiliterate and multilingual repertoires and identities can assist educators in creating supportive literacy environments for youth. It offers recommendations for literacy scholars and educators in this regard. (Contains 2 figures.)