One of the most promising acceleration methods for multi-TeV linear Colliders is the Two-Beam approach which is presently being pursued at CERN. Of primary importance is the choice of acceleration frequency and acceleration gradient. Then the application of two-beam techniques to lower energy linear colliders with the view towards multi-TeV upgrades will be addressed. In order to reduce fixed costs, alternate configurations for the main beam injector and for the drive beam accelerator will be discussed.