The National Register of Historic Places considers properties historic when they are fifty years old. These few pages from this 1958 Chicago and Illinois business directory includes listings for professionals that may be useful to researchers seeking information about properties dating from before 1962.

There are two sets of listings for these categores, for Chicago being the main listing and for the rest of the state being much shorter, at the end of the book.

This clearly is not an exhaustive listing, but is meant to supplement other directories and sources.  It does indicate though some firms active locally that chose to promote themselves by lsitings here--those of Stanley D. Anderson, Edward H. Bennett, Jr., Cone & Dornbusch, Frazier & Raftery (in state section), etc. But absent are Jerome Cerny, who maintained an office in the south tower of Market Square then and was active both locally and nationally, and also I.W. Colburn.  The landscape lsitings do not inlude Helen Milman, Franz Lipp, Margaret Cole Church, Marshall Johnson, or others then active locally and on the North Shore. 

This directory was donated by local historian Shirley McDonald Paddock, Lake Forest.