Exploiting the spin degree of freedom to transfer information or perform logic operations builds the basis of spintronics. There is strong experimental evidence of spin selectivity in helical molecules, which has been traced back to a very delicate interplay between spin-orbit interactions and helical geometry. This novel phenomenon has been called Chirality-Induced Spin Selectivity (CISS) effect. We will carry out in the project computational studies to shed light on the CISS effect from various perspectives. For this, we will combine model-based studies helping to formulate effective Hamiltonians showing the interrelationship between spin-orbit effects and helicity, with advanced Density-Functional-Theory calculations to address molecule-specific spin-dependent properties as well as molecule-substrate interfaces.