The HEROIC project aims at filling the gap between the currently low operation frequencies of printed, organic flexible electronics and the high-frequency regime, by demonstrating polymer-based field-effect transistors with maximum operation frequencies of 1 GHz and complementary integrated logic circuits switching in the 10-100 MHz range, fabricated by means of printing and direct-writing scalable processes in order to retain low temperature manufacturability of cost-effective large area electronics on plastic. The recent development of semiconducting polymers with mobilities in the range of 1 to 10 cm^2/Vs, and even higher in the case of aligned films, suggests that suitably downscaled printed polymer transistors with operation frequencies in the GHz regime, at least three orders of magnitude higher than current printed polymer devices, are achievable, by addressing in a holistic approach the specific challenges set in the HEROIC trans-disciplinary research programme: (i)development of scalable high resolution processes for the patterning of functional inks, where printing will be combined with direct-writing techniques such as fs-laser machining, both in an additive and subtractive approach; (ii)development of printable nanoscale hybrid dielectrics with high specific capacitance, where low-k polymer buffer materials will be combined with solution processable high-k dielectrics, such as insulating metal oxides; (iii)improvement of the control of charge injection and transport in printed polymer and hybrid semiconductors, where high-mobility 1-D and 2-D structures are included in polymer films; (iv)development of advanced printed and direct-written transistors architectures with low parasitic capacitances for high-speed operation. HEROIC will radically advance and expand the applicability of polymer-based printed electronics, thus making it suitable for next generation portable and wearable short-range wireless communicating devices with low power consumption.