[en] The powerful beams of x-ray radiation generated by insertion devices at the Advanced Photon Source synchrotron facility, being constructed at Argonne National Laboratory, will deposit substantial amounts of localized heat on the components they intercept. Undulator radiation, in particular, is confined to a very narrow beam with a very high peak flux. Front-end components which are the interface between the x-ray source on the storage ring and the optical components on the experimental floor must safely handle this power and provide for the protection, safe operation, collimation, transmission, and monitoring of the generated x-ray beams. Front-end components include windows, power filters, slits, photon position monitors, and various beam stopping devices (shutters), all of which must be cooled. This paper is devoted to a detailed investigation of various aspects of window and shutter designs emphasizing alternative design concepts, material considerations, and cooling techniques necessary for handling the unprecedented heat fluxes of the undulator x-ray beams. Alternative designs are thermally and structurally analyzed by numerically simulating full-power operating conditions. These analyses have relevance to the design and development of other beamline components which are also subject to the extremely high heat flux of insertion device radiation