The Bolivian architect Freddy Mamani Silvestre doesn’t have an office, use a computer, or draw formal blueprints. He sketches his plans on a wall or transmits them orally to his associates. Since 2005, Mamani and his firm have completed sixty projects in El Alto, the world’s highest city, which sits at nearly fourteen thousand feet, on an austere plateau above La Paz. In the past twenty years, the economy there has burgeoned, along with an enterprising, mostly indigenous population. Mamani earned his fame building mixed-use dream houses for the city’s nouveaux riches.