The purpose of this work was the investigation of the water vapour transport through thermoplastic dense films of a poly(amide-12-bethylenoxide) such as Pebax(R)2533. Similar polymers have gained a unique position in many technologies for different reasons, such as their good physical properties, high processability, notable strength and transport properties to gases and vapours. Moreover, a rising demand of materials with specific characteristics in terms of water vapour transport comes from various market niches (i.e. textiles, building trade, packaging). For these reasons in this work particular attention has been paid to an elastomeric polymer such as the Pebax(R)2533, an easily process, able mawrial with good transport properties. Previous studies have pointed out that Pebax(R) copolymers can be used as precursors of membranes for separation processes of condensable vapours and gases. In this work a further investigation of the water transport properties through Pebax(R)2533 and derivative films allowed an understanding of their potential applications. The efficiency of these films has been tested by means of vapour permeability, solubility, diffusivity, and hydrophobicity/hydrophilicity measurements. (C) 2003 Elsevier Science Ltd. All rights reserved.