Point defects in crystals are the solid state analog to trapped ions. Thus these “quantum defects” have gained popularity as qubit candidates for scalable quantum networks.  In this talk, I will introduce some of the basic quantum defect properties desirable for quantum network applications and give some illustrative examples of recent successes toward scalable quantum networks, highlighting my group’s work on single NV centers in diamond and shallow donors in ZnO. I will also discuss outstanding challenges (or opportunities) toward scaling quantum systems based on defects, which include photon loss and maintaining spin and optical coherence in integrated devices.