So great, you've elevated your Perl game to a new level by using Test::More, prove, and automated testing. Do you know what percentage of your code your tests actually exercise? Devel::Cover is an outstanding testing tool that needs to be part of every Perl developer's toolbox. This talk will introduce Devel::Cover and explain how to use it effectively using simple code examples from the real world. It will end with some advanced techniques illustrating how Devel::Cover not only can provide coverage, but can also be an incredibly helpful debugging and code development tool.