We suggested the idea of transporters being unable to function in 
warp back in the second-season episode ÒThe Schizoid Man.Ó We realized, 
however, that laying down such an absolute rule would get some future 
writers into trouble, so we took the precaution of suggesting a loophole, 
namely that you could indeed beam at warp, just as long as both the ship and 
the target were at the same warp factor. Sure enough, that very situation 
came up in ÒThe Best of Both Worlds,Ó and Transporter Chief OÕBrien has a 
line in which he confirms that we have indeed Òmatched warp velocity for 
transport.Ó (There probably are occasions where we have indeed broken this 
rule, but we do try to get things right.)  Æ