The authors conducted a rubric assessment of information literacy (IL) skills in research papers across five undergraduate first-year seminar programs to explore the question "What impact does librarian intervention in first-year courses have on IL performance in student work?" Statistical results indicate that students in courses with greater levels of strategic faculty-librarian collaboration performed significantly better in IL outcomes than those in courses with low collaboration. Intensive librarian course support was not necessary to achieve significant learning gains; these tended to occur when librarians provided initial input into syllabus and assignment design, followed by one or two assignment-focused IL workshops.