Have an Answer?
There are so many! Broadly, you might consider working in fundraising/development, communications, human resources, finance, client services, project management, event coordination, or IT. Generally, almost any profession you can think of will have a nonprofit equivalent - e.g. sales and business development share a lot of similarities with fundraising.
The answer to this question will vary so much depending on the organization. To narrow your search, I suggest examining a few organizations you respect, and taking a look at their "Our Team" page on their website to get an idea of the kinds of professions and people they employ.