The majority of devices designed to extract energy from ocean waves operate through exploitation of the buoyancy (Froude-Krylov) and/or diffraction force regimes. Such devices extract energy through interaction with the displacement and/or acceleration of fluid particle motions respectively. By comparison, very little consideration has been given to systems which extract wave energy through coupling with fluid particle velocities. This paper performs a preliminary investigation into the hydrodynamics of a Wave Energy Converter (WEC) that is driven through interaction with the wave-induced fluid particle velocity. In particular, the work focuses on liftbased WECs consisting of a number of wave-driven, rotating hydrofoils. The paper develops a mathematical framework for such a system operating in regular, linear waves in 2D. It is noted that despite the unique nature of the device, it is possible to represent its operation using mathematics which are already familiar to the wave energy sector. The mathematical framework is subsequently used to investigate the performance of a pair of wave-driven, rotating hydrofoils. Results show that power capture efficiencies up to approximately 80% are potentially possible for the particular system considered under the constraints assumed. It is also found that the system is relatively insensitive to variations in design and control conditions. This suggests that further investigation is warranted to determine if lift-based WECs might represent a reasonable means of wave energy extraction.