At the turn of the century, financial circumstances compelled her to begin writing to earn money, and she produced newspaper articles on architecture and interior design as well as stories and serials for such magazines as Harper's, Scribner's, and The Century, as well as light novels, including Flight of the Moth (1904), Purple and Fine Linen (1906), Woven in the Tapestry (1908), The Title Market (1909), and The Eagle's Feather (1910).
She wrote in various styles, including humorous travel books, early in her career. In 1922 her book Etiquette (full title Etiquette in Society, in Business, in Politics, and at Home) was a best seller, and updated versions continued to be popular for decades.
After 1931, Post spoke on radio programs and wrote a column on good taste for the Bell Syndicate; it appeared daily in some 200 newspapers after 1932.
Peggy Post, Emily's great-granddaughter-in-law, is the current spokesperson for The Emily Post Institute — and writes etiquette advice for Good Housekeeping magazine, succeeding her mother-in-law, Elizabeth Post.
Peter Post, Emily's great-grandson, writes the "Etiquette at Work" column for the Sunday edition of the Boston Globe. Peter is author of best selling book "Essential Manners For Men", "Essential Manners For Couples" and co-authored "The Etiquette Advantage In Business" which is in its second edition.
Lizzie Post, Emily's great-great-granddaughter is the first member of the fourth generation of Posts and her book is titled "How Do You Work This Life Thing?" (Collins 2007).