Mosuo women control their own finances and do not marry or live with partners; they practice what they call "walking marriage." A man may be invited into a woman's hut to spend a "sweet night," but must leave by daybreak. While tourism has brought wealth and 21st century conveniences to this remote area, it has also introduced difficult challenges to the Mosuo culture -- from pollution in the lake, to the establishment of brothels, to mainstream ideas about women, beauty and family.