Eventually Hasse's family made its way to southern California where she not only earned the title of "Champion Fast Lady Bicycle Rider of Los Angeles,"[2] but also obtained her first library job.

From 1889 to 1895, Hasse worked under the resolute tutelage of Tessa Kelso, the Head Librarian at the Los Angeles Public Library (LAPL).

[3] Hasse honed her craft through practical experience,[3] diving into her work with a passion and eagerness that she managed to retain for the remainder of career.

The two also worked to make the LAPL more user-friendly by offering free borrowing privileges, adding additional weekend hours, and allowing check-out of periodicals.

While Hasse's work with Kelso significantly improved many areas of the LAPL and earned them high marks with outsiders, the duo increasingly found themselves in trouble with the local library board.

[citation needed] After enduring much harassment, pay decreases, threats to cut library funding, and general moral outrage from the board, Hasse and Kelso resigned from their positions in 1895.

While she was collecting and organizing, Hasse continued to regularly publish not only bibliographies of government publications, but also items of other interest such as "Travel and Exploration" that appeared in List of Books for Girls and Women and Their Clubs.

[17] When the NYPL consolidated its borough branches, it was said to have housed "one of the world's greatest collections of government publications," with items dating back to the American colonies.

[18] Hasse's work developing and classifying this special collection garnered her praise from the top periodicals in the field, most especially from Library Journal, for which she was a regular contributor.

Due to this freedom, she was able to track down the first book ever published in New York (1693), Narrative of an Attempt Made by the French of Canada Upon the Mohaque's Country, which, coincidentally, also happened to be the first government publication as it was written at the request of the governor.

In 1915, the Chief Reference Librarian, Harry Miller Lydenberg, under new NYPL Director Edwin H. Anderson, launched a campaign against her, claiming that her entries were "erroneous or inconsistent.

[26] From 1917 forward, Hasse would struggle because of her German ancestry, support of the women's suffrage movement and equal pay and working conditions, desire to aggressively market library services, and lack of a husband.

Anderson began keeping a file on Hasse, documenting every questionable move she made, even misconstruing legitimate inquiries to suit his needs.

He reported her to the United States Secret Service in 1917 for "suspicious activity," which was largely due in part to her seeking other employment with President Wilson's Inquiry group.

[27] The Inquiry was formed by President Woodrow Wilson to "collect and organize information for the eventual peace conference" that would occur at the conclusion of World War I.

As late as 1922, three years after her departure from the NYPL, Anderson was still reporting her to the Justice Department and even worked with J. Edgar Hoover and the Federal Bureau of Investigation (FBI) to open a file on her.

She finally obtained employment as an instructor at George Washington University and as a research consultant for what would later become the Works Progress Administration (WPA), publishing bibliographies of Social Security information.

From there she worked temporarily for the Temporary National Economic Committee (TNEC) and then as indexer for the Securities and Exchange Commission (SEC), and later still, as a bibliographer for the Immigration and Naturalization Service.

In those fifty-four years, Hasse made a significant mark on the field as a library assistant, indexer, cataloguer, classifier, bibliographer, editorial analyst, and author.