THE SUBJECT OF FREEZE-THAW DURABILITY of concrete was covered in all four previous editions of the ASTM Special Technical Publication on significance of tests and properties; the chapters on this subject in ASTM STP 169, ASTM STP 169A, ASTM STP 169B, and ASTM STP 169C were authored by C. H. Scholer and T. C. Powers, H. T. Arni, H. Newlon, Jr., and H. Newlon, Jr. and T. Mitchell, respectively. Because little has changed in this subject area since the publication of ASTM STP 169C, this chapter includes only minor changes, that is, an update of the reference list and a few revisions in the text, to the version that appeared there.