This article looks at how professional learning communities (PLCs) have become an operational approach for professional development with potential to de-isolate the teaching experience in the fields of science, technology, engineering, and mathematics (STEM). The authors offer a short synopsis of the intellectual origins of PLCs, provide multiple examples of PLCs employed in projects funded by the National Science Foundation (NSF) through its Math and Science Partnership (MSP) program, and consider benefits for varied aspects of the teaching and learning environment. (Contains 1 footnote.)