We review recent work in the field of organic thin films and organic-inorganic interfaces which is relevant for device applications and particularly organic field effect transistors (OFETs). Focussing on the structural properties of these systems we discuss results obtained mostly through X-ray scattering techniques. We address the growth behaviour and interface formation of organic thin films including roughness evolution and crystal structure. In particular, we review real-time studies of pentacene, diindenoperylene, and PTCDA deposition on different subtrates which illustrate their specific growth kinetics. Covering different thickness regimes we show how the molecular orientation depends on the substrate and the growth conditions. Finally, we address the structural properties of organic heterostructures, i.e. metal and insulator films on organics, demonstrating how to assess and control interdiffusion and thermal stability of the capping layers. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)