Part of the mission of CultureMap is to shine a light on all the good work Houston nonprofits do to make our city a better place to live. That's why we're bringing back the CultureMap Charity Challenge, presented by Yellow Cab.

In this challenge, you get to help us select the winning charity for 2015. Here's how it works:

With plenty of input from our own storied society guru Shelby Hodge, CultureMap selected 12 deserving nonprofits to compete for the grand prize as they all raise awareness for worthy causes.

• CultureMap readers can vote for their favorite charity every day, once a day, until Feb. 20 at midnight.
• The winner will be announced on Feb. 23.
• The winning organization will receive an exclusive advertising package from CultureMap valued at $5,000, plus a $2,500 cash donation, $200 gift card courtesy of Yellow Cab and more.

Now it's up to you. Ready, set, vote!