If only Andie and Kelly had had access to a program like DonateMyDress.org. Started in April 2008, it is the first national campaign to encourage girls to donate prom and special occasion dresses to those who cannot afford them. Never underestimate how a simple dress can transform a teen girl.

The program has been the answer to thousands of girls who struggle to afford prom dresses, for which the average cost is $236, according to research done by the Hearst Teen Network. This campaign has been a huge editorial success and provides an innovative way for girls to help their peers in need.

The program has also opened the door to several marketing opportunities. In March, we partnered with a national retailer and celebrity spokesperson, actress Ashley Greene of "Twilight," and encouraged nearly 1,000 girls to drop off dresses in exchange for a 20% discount off a new dress. The donated dresses were then distributed to the 501c3 chapters within our network. We also held a celebrity dress auction on charityfolks.com that raised enough money to establish the Purple Dress Awards, $500 grants given to our most promising chapters. News of Taylor Swift's dress donation was picked up in nearly every major celebrity weekly and brought record traffic to DonateMyDress.org.

All of this sends a clear message to advertisers: Teens care about fashion for a cause (see the September 65th anniversary issue of Seventeen if you need further proof). While teens love doing good, they also love knowing what's in it for them. It makes sense to give a new life to a dress you wore once and be rewarded with discounts and deals that will help finance your next formal occasion.

This Spring Hearst Teen Network conducted a survey and found that 65% of 2,811 respondents nationwide would not cut back on spending for prom gowns because of the recession. What better way to reach teen girls than through cause marketing focused on the one purchase they are bound to make?

Whether a teen spends a couple hundred dollars on her prom dress or receives one for free, our goal is to be a part of her lifelong memories (not to mention her Facebook profile picture, Twitter avatar, flickr albums, YouTube media mixes...). The key lesson: Never underestimate the power of a dress to drive success or the will of a teen girl to make things happen.

This commentary is insightful. I recommend it to others.