Bobbi Brown has taken over StyleList this week as Guest Editor and we couldn't be more thrilled! From Bobbi's tips for looking gorgeous in glasses to the beauty expert's Pretty Powerful Campaign for Women & Girls, we're in awe of not only her mastery of the makeup brush, but also inspired by her philanthropy.

One Bobbi Brown product we're absolutely in love with this spring is the Pretty Powerful Mascara, with every cent of the $25 retail price directly donated to The Girl Rising Fund, a 501c3 fund operated by the TIdes Foundation, which removes barriers to education that many girls face in developing nations.

Read more about the Pretty Powerful Campaign here and enter our giveaway below for a chance to win your very own bottle of Pretty Powerful Mascara!

Today only we're giving away 10 Bobbi Brown Pretty Powerful Mascaras to 10 lucky StyleList readers on Twitter! It's easy to enter: all you have do is follow @BobbiBrown and @StyleList on Twitter and retweet 1 of 10 promotional tweets for a chance to win!

Full rules:
• Open to legal residents of 50 United States and the District of Columbia who are 18 and older.
• To enter, retweet (true retweet, quoted retweets will not be counted) 1 of our 10 tweets stating "Retweet for a chance to win 1 of 10 @BobbiBrown Pretty Powerful Mascaras! Rules: [LINK] #StyleListSelects".
• Contest begins on March 20th, 2014 at 12:01 AM Eastern Time and ends on March 20th, 2014 at 11:59 PM Eastern Time.
• You may enter up to 10 times.
• 10 winners will be selected in a random drawing at the end of the contest.
• 10 winners will each win (1) .17 oz Bobbi Brown Pretty Powerful Mascara with an approximate retail value of $25.00.
Click here for complete Official Rules