The importance of effective reading instruction in the primary grades cannot be overstated. Teachers are expected to be qualified and capable literacy teachers to produce proficient readers (Bornfreund, 2012; Walsh et al., 2006). The purpose of this study was to explore Pennsylvania kindergarten, first, and second grade teachers' perceptions, attitudes, and knowledge regarding early literacy skills incorporating the Science of Reading (SoR). A gap in the literature leaves unanswered questions as to why inservice elementary teachers in the classroom lack knowledge of the SoR and the methods needed to successfully teach students early literacy skills. This mixed methods study explored kindergarten through second grade teachers' (n = 126) self-efficacy, early literacy knowledge, professional development opportunities, and ways SoR is reportedly integrated into early literacy lessons. This particular study uncovered significant findings which included low early literacy knowledge (60% average score) from the sample while having average self-efficacy beliefs. Also, low professional development opportunities were offered to participants from school districts. All interview participants reported ways that they incorporated SOR into their literacy lessons which aligned with research. Interviewed participants had average early literacy knowledge (73% average score) and average self-efficacy beliefs. Interview participants shared that they have experienced helpful professional development opportunities that aided in their understanding of the SoR. [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.]