Information literacy is widely understood to be a critical component of the educational experience of secondary school students and prepares them for success in school and in life. Information literacy is the ability to acquire, manage, and evaluate information flows, with an emphasis on determining what information is appropriate for a given information need, how useful and credible that information is, and then using that information in an effective and ethical manner. Various secondary education standards establish the need and requirement for high school students to graduate with a set of functional information literacy skills, yet high school graduates have a range of information literacy competencies that may be inadequate. This study examined the perceptions high school classroom teachers have of the information literacy competency levels possessed by their students and the interconnectedness of those perceptions with the level of visibility of the school library and the level of collaboration those teachers have with school librarians in five states in the Mountain West region of the United States using an explanatory sequential design. This mixed methods study utilized an online survey to collect quantitative data and in-depth interviews to gather qualitative data. The survey, which was developed by merging and modifying two previously published instruments, used Likert-like and open-response questions. Pilot testing confirmed validity and internal consistency. In all, 115 participants completed the first two sections of the survey and 27 participants completed the entire survey, which consisted of three sections: demographics; teacher perceptions of student information literacy skills; and teacher relationships with the school library and librarians. Five participants, one from each of the five states included in the site, self-selected to participate in follow-up interviews. The survey consisted of 68 items related to information literacy perceptions and their relationships with the school library. Survey data showed that the correlation between teacher information literacy perceptions and library relationships was significant. Qualitative data collected from the follow-up interviews corroborated the survey data. Overall, the study findings revealed teacher perceptions of student information literacy (IL) skills competency that were average and support for collaboration between teachers and school librarians. [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.]