In Finland the question of appropriate wastewater treatment in rural areas has become very prominent during the last years. The new Environmental Protection Act stipulates that wastewaters must be treated to the extent that they cannot have a negative impact on nature. The Ministry of the Environment is currently preparing a decree specifying the requirements. The draft of the decree proposes that on-site treatment units should decrease the BOD load by 90, total phosphorus load by 85 and total nitrogen load by 40 per cent. To meet the new requirements, the old systems that include septic tanks only need more efficient wastewater treatment methods. Whatever technical solution is selected, the house owner must pay for it. At the moment, even the septic tanks are emptied and maintained irregularly. More sophisticated wastewater treatment methods definitely need more maintenance, which cannot be made the sole duty of the house owners. One potential organisational alternative for managing wastewater treatment in rural areas is the co-operative. Finland has one such pioneering co-operative formed for on-site sanitation. Varsinais-Suomi Water Services Co-operative provides the house owner with professional assistance in wastewater treatment at a reasonable cost. Suvisaari Water Services Co-operative is another new organisation selling sewerage services to its members. But its technology is different: this co-operative operates an LPS-sewerage system instead of on-site treatment.