Abstract: A glue is disclosed which comprises a solution of at least one water-insoluble synthetic organic polymer, such as PVC or ABS, in a solvent which essentially consists of one or several compounds selected from the group consisting of 5- or 6-membered water-miscible lactones or lactams having a melting point of at the most -10.degree. C., a boiling point of at least 200.degree. C. and a flash point of at least 90.degree. C., such as N-methyl-2-pyrrolidone or .gamma.-butyrolactone. The polymer or polymers may be present in a concentration of between 0.5 and 50% by weight, in particular about 10% by weight.The glue may be used at tropical temperatures without problems arising from solvent vapours and without fire risks. The glue is particularly useful for gluing soft PVC articles to hard PVC articles without loss of the soft character of the soft PVC, and for gluing different polymers, such as PVC on polycarbonate or polycarbonate on polyacrylate.