During the last few years the Dutch Butterfly Foundation is receiving fewer observations of the threatened Large Copper (Lycaena dispar batava). Die decline has been related to changes in the marsh areas, concerning succession, acidification, lowering of groundwatertable and management. Therefore in 1998 the “Survival Plan” for the Large Copper was started to improve habitat conditions. This project implicates a survey of the status and area in the Netherlands, perspectives of habitat-development, advice on applied nature management and monitoring. Emphasis is laid on the management of locations, where the eggs were laid; open fen vegetations. In 1997 and 1998 only 24 locations with oviposition in three nature reserves are reported. Development of new habitats has been stimulated. Implementation of management and development of new habitats in close cooperation with the managers of nature reserves is necessary for recovery of this butterfly.