Laser-wires will be one of the essential components within the arsenal of beam diagnostics that will be required at the ILC.  One of the challenges is to achieve micron-scale laser-spot sizes in order to be able to scan micron-scale transverse electron bunch profiles.  Another challenge is to achieve very fast scanning in order to determine the bunch profile at several points within the ILC bunch train.  These challenges are discussed in some detail and an overview of ongoing R&D provided.