Introduction -- Sludge management in highly urbanized areas -- Australia: New South Wales -- Australia: Sydney -- Austria -- Belgium: Flanders -- Bulgaria -- China: Tianjin -- Chinese Taiwan -- Denmark -- Egypt -- European Union -- France: Eastern France, Franche Compte Region, City of Besançon -- France: Eastern France, Lorraine Region, Maxeville and Laneuveville -- France: Southeast of France, coastal area -- Greece -- Hong Kong -- Italy -- Japan: Sapporo -- Japan: Tokyo -- Japan: Yokohama -- The Netherlands -- New Zealand: Wellington -- Norway -- Singapore -- Slovakia -- South Africa -- Sweden: Göteborg -- Switzerland -- Tunisia -- United Kingdom: Eastern England -- United Kingdom: Northern Ireland -- United Kingdom: Northumbria -- United Kingdom: Wales -- United Kingdom: West Scotland -- USA: General -- USA: Arkansas -- USA: Central Maine -- USA: Idaho -- USA: Charlotte, North Carolina -- USA: Northeastern States -- USA: Oklahoma -- USA: Pennsylvania -- USA: Southeastern Virginia -- USA: Washington -- USA: Wisconsin