Karen is the executive director of the Software Freedom Conservancy, a non-profit organization that provides home for free and open source software projects, such as git, samba, QEMU, selenium, inkscape and more. Karen is a professional lawyer and is known for her advocacy for free software, particularly in relation to the software on medical devices. Prior to joining Conservancy, Karen served as an executive director of the GNOME Foundation. Before that, she was general counsel of the Software Freedom Law Center.

Karen co-organizes Outreachy, the award-winning outreach program to draw more women and people of color into Free and Open source software. In addition to her work at the Software Freedom Conservancy, she is also a pro bono counsel to the FSF and GNOME. Karen is a recipient of the O’Reilly Open Source Award and co-host of the oggcast ''Free as in Freedom''.