The New York Public Library is one of the city’s most prestigious charities, with patrons from Brooke Astor to hedge fund billionaires such as Stephen Schwarzman. The Brooklyn Public Library has to try a little harder.

Now, in an effort to enhance its ability to raise private money, the Brooklyn Public Library is moving to a governance structure closer to that of the NYPL. Where the BPL formerly had two boards — a “public” board that handled policy and operations, and whose members were appointed by the mayor and borough president, and a “private” board that handled fund raising, whose membership was self-perpetuating — it now has one 38-member board to do everything. The new, larger board met for the first time last night.

The merger was motivated by a desire to eliminate redundancies, as well as a wish to focus the entire board’s efforts on private fund raising, the board’s president, Thomas Amon, said. Although the city’s three library systems — New York, Brooklyn, and Queens — learned this summer that they would get funding from City Hall to restore six-day-a-week service, Mr. Amon said that the library can no longer depend merely on public funds.

“Generally speaking, if you want to provide enhanced services and programs, you have to rely on private money,” he said. The former chairwoman of the private board — known as the Brooklyn Public Library Foundation board — Janet Offensend, said that a single board is the “normal structure” for a not-for-profit. She said the members of the foundation board wanted to be involved in policy, and to “engage the broad group of the board in fund raising, and generally resource-raising: making friends, raising public funds and private funds.”

Mr. Amon said it was an “optimistic” time for the library, which appointed a new, young executive director, Dionne Mack-Harvin, in March. The library has also just completed a $16.5 million construction project, which included a renovation of the outdoor plaza in front of its central branch at Grand Army Plaza, and a new auditorium and exhibition space, called the Dr. S. Stevan Dweck Center for Contemporary Culture after the major donor to the project.

With the additional funding from the city, the library has budgeted for 140 new staff positions, and already filled 129 of them, Mr. Amon said, adding: “We have a very aggressive plan to get to six days a week by January.”

But there have also been setbacks. In May, the city announced it was scrapping plans for a $135 million Visual and Performing Arts Library designed by Enrique Norten, which was to have been part of the BAM Cultural District. The Brooklyn Public Library had not been able to raise the funds.

Ms. Offensend said that, given the large number of branch libraries in need of maintenance, a project on the scale of the arts library did not make sense. “We are still hoping to have a presence in the BAM Cultural District of some sort or other; it’s just not likely to take that particular form.”

Putting the arts library plan on hold “was the right thing to do,” Mr. Amon said, while acknowledging that “there were some expectations built up.” But, unlike Ms. Offensend, he left the door to reviving the plan slightly ajar, saying: “Who knows? With the right financing structure, it may very well come back.”