Over the last 10 years, organic field-effect transistors (OFETs) have moved to an emerging technology enabling electronic functionalities to be integrated on flexible, plastic substrates. Acceptable electrical performances are now achieved with relatively good stability at ambient air. A lot of work has been devoted to study degradation of device characteristics under bias stress conditions but only few papers deal with the mechanical and thermal effects. In this paper, we review our first reliability results obtained on organic thin-film transistors under mechanical and thermal stresses. The variations of electrical characteristics under bending tests, both in compression and tension, have been studied. Using a specific equipment, we have also evaluated the reliability of transistors under cyclic bending tests. The stress dependency of the transfer characteristic deviates from the one observed for inorganic material like silicon. Possible explanations will be discussed. Finally, thermal step stresses from 110 C to 160 C have been done to evaluate the robustness of the devices. Catastrophic degradation has been observed at 160 C. Work is still in progress to understand the physical mechanism. 2010 Elsevier Ltd. All rights reserved.