TRB’s National Cooperative Highway Research Program (NCHRP) Synthesis 339: Centerline Rumble Strips (CLRS) examines current design, installation, configuration, dimension, and visibility issues associated with CLRS.  The report addresses the need for guidance on warrants, benefits, successful practices, and concerns such as external noise and the reduced visibility of centerline striping material.  Also addressed are pavement deterioration, ice buildup in the grooves, adverse impact on emergency vehicles, and the effect of CLRS on bicyclists.  Particular attention was paid to available before-and-after CLRS installation crash data to document the safety aspects of CLRS and the availability of policies, guidelines, warrants, and costs regarding their use and design.  This topic is published at https://www.trb.org/news/blurb_detail.asp?id=4860