In an attempt to create a rationale for Professional Learning Communities (PLCs), schools have dedicated time to improve teacher collaboration. It is shown that time in PLCs can be reflective, collaborative, and overall inclusive with learning being a top priority among teachers. PLC groups are intended to enhance student teaching and improve teacher retention. PLCs have shared leadership, shared vision, values, collective learning, supportive conditions, and shared practices; all of which play a critical role in the success of a total PLC. Indifferent to the findings for what positive attributes make an effective PLC, schools seem to lack a clear-cut direction for identifying effective PLC attributes. Even when some of these attributes can be noted, there is still a need to better comprehend the protocols, supports, and positive attributes that directly influence success. This qualitative study was designed to determine the attributes of a successful PLC at the secondary level. The researcher explored the views and experiences of secondary Math and Science teachers at Rounds High School. Teachers were asked questions related to unity, teamwork, communication, protocols, PLC support, effective training, and teacher support needed. The participants in this study were eight teachers from math and science who actively were participating within their PLCs, all from Rounds High School. The teachers voluntarily participated in two focus groups dedicated to either math or science PLCs. The focus groups were audio-recorded and transcribed before being analyzed and then deleted after transcription was complete. The findings of the study identified the attributes that led to a healthy and effective PLC. Findings showed the attributes which impacted PLCs were communication, trust, continuity in subject matter, colleague relationships, a supportive administrative team, and clear-cut expectations. With these findings, teachers would feel more valued and have more commitment to the school and its overall success. This success will ultimately improve teacher retention and student achievement school-wide. The teachers shared stories and experiences, as well as the perceived examples of effective attributes while engaging in professional learning communities. The findings can be used to assist other educators in PLCs to better prepare for the implementation of PLCs and what attributes to avoid. [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://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]