Substitute teachers play a major role in assisting students in the absence of regular teachers. However, there is limited evidence regarding the role of substitute teachers in K-12 faculties. The main purpose of the study was to examine the lived experiences and perceptions of substitute teachers regarding their roles in K-12 faculties in rural and urban Pennsylvania school districts, and their involvement in the education system. The current study employed a phenomenological enquiry approach to explore the roles of substitute teachers in public schools in Pennsylvania. Semistructured interviews were used to collect qualitative data on the lived experiences and perceptions of 10 substitute teachers on their roles in K-12 faculties in rural and urban Pennsylvania school districts. The collected data was analyzed qualitatively using NVivo 12 software to construct emerging themes. Seven primary themes were derived from the qualitative analysis: Motivation in substitute teaching is informed by extrinsic and intrinsic factors, substitute teacher's role in student learning, key challenges that substitute teachers encounter, interaction with school members and staff, substitute teachers' attitudes and feelings, substitute recommendations, and causes of shortages of substitute teachers. The findings have a potential to influence policymaking in the education sector in Pennsylvania and guide the planning for long-term needs of substitute teachers. [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.]