Yes! Magazine media bias rating is Left.

Yes! is a non-profit, ad-free magazine that covers topics of social justice, environmental sustainability, alternative economics, and peace. The magazine is published by Positive Futures Network, founded by David Korten and Sarah van Gelder; Korten's wife, Fran Korten, is the publisher. The first issue of the magazine was published in winter 1997.[1] It has ISSN 1089-6651 and LCCN 96656670 sn 96044464.

Source: Wikipedia
http://en.wikipedia.org/wiki/Yes_Magazine