Abstract Guiding of the X-ray photons emitted in an Inverse Compton Scattering (ICS) device is possible using small diameter tubes. Whereas guiding of the electron and laser beams can directly increase the flux output of ICS interactions, manipulating the beams’ propagation can be very challenging. Guiding the output X-rays can be straightforward and offers three enhancements of the usable flux: off-axis X-rays are collimated along the tube; out of bandwidth photons are not guided and therefore filtered out; and, the guiding can be extended far from the interaction region towards the intended application. A tube, acting as a waveguide for the X-rays, can increase the brightness relative to free space propagation by the square of the number of reflections. We present preliminary calculations of the guiding mechanism and explain why Liouville's theorem is not violated. Typical achievable parameters and application scenarios are also described including practically realizable waveguides and materials.