The joint recipients of the 1998 Volvo Environment Prize are Professor Malin Falkenmark and Professor David Schindler for the outstanding work which each has carried out independently on freshwater quantity and quality respectively, both features of profound importance to human society world-wide. The importance of their work becomes greater every year as the world water supply comes under ever increasing stress, threats which the laureates have long recognised, calling for environmentally sound action on water management.