Teacher knowledge in early literacy instruction has been questioned in the field for over 20 years. A theoretical framework outlined by Chall, coupled with the findings of the National Reading Panel, provides a strong foundation for the disciplinary knowledge required to teach children to read. The Basic Language Constructs Survey, a tool developed by Cantrell, Joshi, and Washburn, was designed to evaluate teachers' knowledge, skills, and perceptions associated with the language and literacy concepts necessary for early literacy instruction. Developers of this instrument have reported findings of a study exploring the psychometric properties of the survey and investigations using the tool with college professors and preservice teachers; however, no evaluations to date have been conducted with practicing teachers. Using the Basic Language Constructs Survey, this study examined 65 practicing K-8 teachers' perceptions, knowledge, and skills of the basic language constructs necessary for early literacy instruction and for assisting students experiencing reading difficulties in grades three and above. The investigation revealed limited disciplinary knowledge among practicing teachers in the areas of phonological awareness, phonemic awareness, phonics, and morphology. Results revealed that success rates for participants were higher on skill-based items as compared to knowledge-based items. Findings also indicated that teachers' estimates of their knowledge were aligned with their actual knowledge. Suggestions for using results to guide teacher professional development and directions for future research are also provided.