One of the most interesting European artist of the first decades of the 20th Century is the German musician Kurt Schindler (1887-1935). His strong personality led him to participate intensively not only in the European cultural life of his time but also in the ?happy twenties? of the New York atmosphere, through the concerts of the Schola Cantorum, Carnegie Hall, private parties by the Manhattan personalities of that moment and the experimental theatre of The Neighbourhood Playhouse. His legacy represents a real main source for former studies of cultural heritage for its big amount of direct documentation about the period he lived: his rich epistolary with important artist and cultural patrons, his collection of photographs from all over the world, programs and posters of cultural events in USA and Europe, his field works and compositions, etc. The importance of his legacy, which is spread it out in different archives and libraries mainly in USA, Spain, Germany, Italy and Great Britain, led us to do a proposal in order to offer it to all researchers interesting in this source. The international project, ?La canci?n popular en los trabajos de campo, fuente de inspiraci?n. Contextualizaci?n de fuentes musicales espa?olas y europeas y recepci?n en Am?rica: origen y devenir (1898-1975)? (sponsored by the Spanish Ministerio de Econom?a y Competitividad) is working and researching with this material since 2003; now, the main universities involved are Salamanca, Burgos, Coru?a, Murcia, Alicante, Barcelona (from Spain), Heidelberg, Sof?a, Padua, Graz and Universidad Aut?noma de M?xico. Our proposal is digitalize all this material and offers to the science community.