Negotiate generations-old mountain tracks and cascades of rice paddies to the villages of the H'mong people, an ethnic minority in Vietnam. Trek with Sapa O'Chau – the name means 'Hello Sapa' in the H'mong language – and you'll be boosting the education and literacy of young H'mong tour guides. Sapa O'Chau is headed by Shu Tan, an energetic H'mong woman making a real difference for her people, and if you're keen on a longer stay in Sapa, she's always looking for volunteer teachers at Sapa O'Chau's community school.