In 2015 Milan hosted the Universal Exposition; the themes were technology, innovation, culture and traditions concerning food. Participants in the Expo included 145 countries, three international organisations, several civil society organisations, several corporations and non-governmental organizations (NGOs). The participants were hosted inside individual or grouped pavilions. In June 2010 Sala was appointed CEO of the Expo, which led to the nickname "Mr. Expo" in the following years.