The Gunnery in Washington will present a program with Patrick Meier, a National Geographic emerging explorer, on Wednesday, Oct. 29.

Meier will speak about crisis mapping in the lower gym of the school, 99 Green Hill Road, at 7 p.m.

Crisis mapping is a way to harness available technology and the power of the social media to assist humanitarian aid efforts in a swiftly developing crisis such as the Haitian earthquake or floods in Pakistan or a war zone in Libya.