Bacteria and bacteriophages have been locked in an expansive and long-running arms race, with each side constantly angling to gain the upper hand. Of the myriad anti-phage defenses bacteria evolved, CRISPR-Cas systems stand out as the only known defenses to exhibit adaptive immunity. While these systems are best known for the Cas9 nuclease synonymous with CRISPR technologies, CRISPR-Cas systems hold far greater functional diversity. This diversity allows the systems to offer different defense modes against various invaders, but they also provide distinct mechanisms for technology development. In this talk, I will describe my group's work exploring the rich functional diversity of CRISPR-Cas systems and how they can be harnessed to benefit humanity.