The days of the relational database being a one-stop-shop for all of your persistence needs are over. Although NoSQL databases address some issues that can’t be addressed by relational databases, the opposite is true as well. The relational database offers an unparalleled feature set and rock solid stability. One cannot underestimate the importance of using the right tool for the job, and for some jobs, one tool is not enough. This talk will focus on the strength and weaknesses of both relational and NoSQL databases, the benefits and challenges of polyglot persistence, and examples of polyglot persistence in the wild.