Sergio Arturo Castro MartÃnez (born March 12, 1941) is a Mexican humanitarian who resides in San Cristóbal de las Casas, Chiapas, Mexico.He is by training an agricultural engineer, teacher and veterinarian.
However, by nature he is a true humanitarian, ethnologist and polyglot (languages include Spanish, French, Italian, English, Tzotsil, Tzeltal and Mayan fluently).
Sergio has spent more than 45 years helping to build schools, develop water treatment systems and provide wound care for burn victims for the many indigenous cultures and Mexican people of Chiapas.
He travels daily to the surrounding indigenous villages and marginalized urban areas to care for the health and social development needs of the under served.