Zee Nunes shot the covers. (source)
Click here to view last year cover featuring Ari Westphal, here to view 2015 cover featuring Amanda Wellsh, here to view 2014 cover featuring Alessandra Ambrosio, here to view 2013 cover also featuring Alessandra Ambrosio, here to view 2012 cover featuring Carola Remer, here for 2011 cover with Freja Beha Erichsen, and here for 2010 cover with Barbara Berger.
The cover with Lorena Maraschi is shot by Sofia Sanchez and Mauro Mongiello. The one with Julie Hoomans is by Victor Demarchelier, while the black and white cover is by Mathieu César. (source)
Click here to view last year cover featuring Jessica Miller. Click the links to view 2014 covers featuring Constance Jablonski, Karen Elson and Sasha Luss, here for 2013 cover with Sasha Luss, here to view 2012 cover featuring Lindsey Wixson, here for 2011 cover with Daphne Groeneveld, here for 2010 cover with Monika Jagaciak, and here for 2009 cover with Karen Elson.