Written language occupies a uniquely important space in the university. The present investigation concentrates upon variation in the situations and language that characterize the different varieties of writing produced at the undergraduate level in the English department. The aim of such an investigation is to identify and characterize the registers, or varieties of language that accompany different situations and functions (Biber, 1995), that constitute the range of written work produced by students during undergraduate courses in the department in which writing is commonly taught and especially important. This research contributes to the explication of the situationally and linguistically rich domain of undergraduate writing generally, and English-department writing specifically. The first component of the present study is an analysis of the non-linguistic, situational characteristics of the assignments given to students across the levels and subdepartments of undergraduate coursework in the English department. First, the syllabi representing all course offerings within the department from the previous two academic years were collected. Assignment descriptions informed the bottom-up generation of a set of register categories representing all written assignments found in the syllabi. For comparison, this process was also undertaken for available syllabi from the Mechanical Engineering and Anthropology departments. In the English department, subdepartment-area expert informants were consulted and groupings were refined into a comprehensive taxonomy of department registers. Registers were then analyzed according to their frequency patterns across levels and subdepartments, described qualitatively, and clustered according to communalities with previous studies. The second part of the study entailed the collection of written assignments from students, which were then grouped into the register categories and assembled into a corpus. The registers of this corpus were then investigated using multidimensional analysis (Biber, 1988) and for patterns of linguistic complexity using the Biber, Gray, and Poonpon (2011) framework. The findings of this study suggest that undergraduate English writing contains a large degree of situational and linguistic variation. Situationally, registers of the English department differed from department-external points of comparison and between different subdepartments of English in both frequency across years and qualitative characteristics. Linguistically, the registers investigated exhibited three dimensions of variation with differences by register and subdepartment more than across levels as well as patterns of difference in complexity-feature frequency. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]