TRB's National Cooperative Highway Research Program (NCHRP) Synthesis 299: Recent Geometric Design Research for Improved Safety and Operations reviews and summarizes selected geometric design research published during the 1990s, particularly research with improved safety and operations implication.

In 2012, TRB released NCHRP Synthesis 342 as an update to NCHRP Synthesis 299.  NCHRP Synthesis 342 reviews and summarizes roadway geometric design literature completed and published from 2001 through early 2011, particularly research that identified impacts on safety and operations.