CONTRABASS stands for Ferroelectric control of Rashba states, a 42 months ANR project starting in December 2020. Spintronics devices involve ferromagnetic elements with high switching energies. Contrastingly, the polarization of ferroelectrics can be easily switched by an electric field, at energies typically 1000 times lower. Combined with high spin-orbit coupling elements, ferroelectrics have also a natural potential to generate a strong Rashba effect, which could allow obtaining an electrically-switchable, highly efficient spin-charge interconversion. The CONTRABASS project gathers five partners with complementary expertise in metal spin-orbitronics, oxide spintronics and spin-resolved photoemission, with the aim to demonstrate the ferroelectric control of the charge-spin conversion in Rashba heterostructures, and to explore its potential for applications, at the cross-road between spintronics, ferroelectricity and quantum materials physics.