Reed and grass are widely used in many traditional building cultures all over the world. They are easy availability and good material properties have made them a popular component in roof, wall and other constructional parts of houses. In some areas whole buildings are built out of reed, and in other areas again it is used in combination with a variety of other, mostly natural, building materials. After presenting different examples of the use of this special material from Oce-ania, Asia, Africa and America, we will focus on the harvest, processing and use of reed in the middle-European region. The use of reed in traditional architecture is mostly connected with the lowland regions of Europe, as in mountainous areas wood as construction material and especially wooden shingles as thatching were always given advantage over the slightly more ephemeral reed. Also the fact that in mountain areas less reed is available and in the lowlands wood is scarce led to the evolution of a very typical appearance of lowland villages with reed thatched houses. It is important to note, that according to availability of reed and peculiarities of agricultural production, in some areas rye straw could even be more important than reed. Usually in more hilly and mountainous areas rye straw was more easily available. However, with the introduction of mechanised harvest processing the resulting rye straw was not of good quality anymore, and therefore from the beginning of the 19 th century reed was the only organic thatch alternative. Especially in the Carpathian basin and around Lake Neusiedl the use of reed has a long tradition. This tradition continues until present day, albeit on smaller dimensions and somewhat transformed compared to the ” ethnographical ” past, when only natural materials were used in rural architecture. Today it is at least as expensive to cover a building with reed as with ceramic tiles. While of course ceramic is fireproof, there is a discussion going on concerning overall fire resistance qualities of reed thatch. However many people feel still attracted to the peculiar appearance of the more traditional material, and commission the use on newly built houses. In some special areas, which are under cultural heritage protection, only the use of this traditional material is allowed. Even so, the total number of buildings with reed roofs has decreased to a small amount, which means, that there are only a few craftsmen left, who are still adept in reed thatching techniques. One aim of our research was to get an insight into the working procedure of these craftsmen. Interestingly the modern building industry also uses a number of products manufactured out of reed – usually they are used as composites in combination with other building materials – reed mats as reinforcement under plaster layers or to enhance insulation properties. As Lake Neusiedl is not only a local, but also a major source of reed for the middle-European region (a substantial part of the harvest is exported to the Netherlands and Germany) the traditional and present use of reed as building material in its surrounding is worth to be studied more thoroughly. 83 In: Csaplovics, E., Schmidt, J. (eds.) (2011): International Symposium on advanced methods of monitoring reed habitats , Rhombos Verlag Berlin. pp. 83-108.