We present in this paper data about the popular uses of elder (Sambucus nigra) obtained in two ethnobotanical studies carried out in the districts (comarques) of Pallars Jussà and Pallars Sobirà (Pyrenees) and in the Montseny Massif (Catalan Prelittoral Range), complemented with others from different Catalan regions (also investigated by our group) and compared with those from other Iberian and Mediterranean territories. This bush or small tree belonging to the family Caprifoliaceae is one of the plants that have been most reported and used (for medicinal and other purposes) by the informants, not only in the two regions studied but in all Catalonia and in many Mediterranean areas as well. It is one of the most versatile of plants, being used for food, medicine, crafts and games, as well as for ornamental purposes. In addition, almost every part of the plant, including the bark, roots, leaves, flowers, and fruit, has some uses.