TIANJIN, July 8 (Xinhua) -- Global Mayors Dialogue -- SCO Summit Cities opened in north China's Tianjin on Tuesday. Guests including mayors, diplomatic envoys and experts from different countries were brought under the same roof to share their opinions on how Shanghai Cooperation Organization (SCO) member countries can further deepen practical cooperation in fields such as interconnection, trade and investment, green development, and people-to-people exchanges.