Haon’s professional statement also indicates that she designed for Harvey Berin, a Seventh Avenue ready-to-wear label known for adapting Parisian fashions, between 1937 and 1946. However, there do not appear to be any records confirming her employment at the label. Design sketches and patterns in the collection indicate that she produced designs for New York fashion label Larry Aldrich between 1941 and 1945 (or possibly longer).

In addition to work for Berin and Aldrich, Haon led a team of over ten sketch artists and designers by 1941, possibly for her own label, Dorothy Haon Modes, which is shown on receipt stationery within the collection. Records from the U.S. patent office also show that both Dorothy and her sister Marion were granted patents for dress designs between 1939 and 1941.

In 1947, Haon began designing for Betty Junior Dresses and Margot Dresses, Inc., a manufacturer of fashionable junior apparel.

In the early 1950s, Haon began working for the New York showroom of Eleanor Beard Studios, a hand quilted linens firm based in Hardinsberg, Kentucky. Established by Eleanor Beard in 1921, the firm employed local women to craft comforters, quilts, sleepwear, sweaters, and decorative home accessories for sale in metropolitan areas, including New York City, where the Eleanor Beard showroom was located on Park Avenue. When Beard died in 1951, Clara Kjose, manager of the New York store, became head of the company. A note written by Haon indicates that she may have begun her association with Eleanor Beard Studios while the founder was alive. It is unclear if Haon was acting as an Eleanor Beard Studios representative while designing for Margot Dresses. She reports no affiliation with the company in her personal statement.

In March of 1954, Haon began serving as the Southampton (Long Island) representative of the Eleanor Beard New York showroom. Haon set up a retail space on Job's Lane, a fashionable shopping district in the Hamptons resort community, and managed the seasonal showroom into autumn. In addition to ordering and selling merchandise on consignment, she proposed patterns and fabrics for clients requesting custom work, such as recovering comforters. Although the shop was known for its home décor items, records show that a large percentage of the merchandise sold by Haon was clothing and accessories, including skirts, shorts, beach capes, sweaters, and neckties. Haon’s ability to sell custom fashion pieces is presumably related to her experience as a designer in the previous decades.

Correspondence from 1955 suggests that the relationship between Haon and Kjose soured. There seems to have been miscommunication and confusion caused by the fact that the Southampton store was somewhat isolated from the other Eleanor Beard offices, which led to tension and accusations from Kjose that offended Haon, including a heated debate over whether or not Haon was using the Beard brand name inappropriately. A draft of a personal letter to a client from around this time indicates that Haon left the Eleanor Beard shop due to “differences” with Kjose. Records also indicate that Haon worked on a decorator’s commission basis with private designers such as Dorothy McCausl[illegible] while she was planning to leave the Eleanor Beard shop, although it is not known whether this business relationship continued after she left.

It is unclear what direction Dorothy Haon's professional life took during the latter half of the 1950s. From 1960 until 1992, Haon is known to have been employed as a representative of Marion Heath Greeting Cards, although records exist that indicate that Haon was selling merchandise under the Eleanor Beard brand in 1976, possibly as an independent sales representative. Correspondence concerning these items was sent to Haon in Wilmington, Delaware, where she presumably lived at the time.

Haon may have also maintained an importation business. Among her papers is letterhead identifying, "Dorothy Haon Importations, 17 East 48th Street, NY, NY.," as well as personal notes that include other possible names for her own antique and interior design business that may or may not have been used. In 1996, Christie’s auctioned a group of antique European furniture and sculpture pieces belonging to Haon’s estate.

Dorothy Haon died in 1995 at the age of 97.

Less is known about the career of Dorothy's sister Marion, although it appears that she designed in partnership with Dorothy throughout the 1930s and 1940s (and possibly before that). It is also known that the sisters lived together at 300 Park Avenue in New York City starting in 1939.

There are also records from the U.S. Patent Office that show dress designs attributed to Ruth Haon, presumably a relative, filed in 1939. Correspondence from Dorothy’s time working in the Eleanor Beard shop indicates that Ruth Haon was paid commission by the Beard brand for interior decorating in 1954 and possibly after.

The Eleanor Beard business records originate from Dorothy Haon's managerial experience at a seasonal Eleanor Beard showroom in Southampton, Long Island, during the summer months of the mid- to late-1950s. The Eleanor Beard records include an accounting ledger, commission records, fabric samples, invoices, receipts, promotional materials for the Southampton shop, detailed customer records and correspondence, and correspondence with other Eleanor Beard representatives (in Manhattan and Kentucky).

The fashion design records include numerous pencil sketches and muslin patterns as well as ephemera in the form of annotated business cards, press clippings, invitations to Parisian fashion shows, and other printed materials advertising primarily Parisian wholesalers and retailers. The Haon sisters probably gathered these materials during their trips to Paris between the 1920s and 1940s to purchase materials or to copy the latest French fashion designs. During the early to mid-twentieth century, “translating” French designs for American consumers was a widespread practice by American fashion designers like Haon.

Overall, the collection provides useful information about American fashion during and after World War Two, as well as insight into the world of high-end merchandising and women-owned business enterprises.