“Waste water/ sludge Treatment- Recover national precious natural resources”. It was the working topic of the leaders of Leipzig and Hanoi Cities on March 22, 2019 at the Office of Hanoi People’s Committee. German Delegation Head was HE Dirk Panter, PM of Sachsen State. HE Kristian Kirpal, Chairman of Industrial and Commercial Chamber of Leipzig, and the leaders of great businesses from Germany. From Vietnamese side, Mr. Nguyen The Hung, Deputy Mayor of Hanoi and departmental heads were present at the meeting.