The Children’s National Medical Center in Washington received $150 million last week from the United Arab Emirates.

The donation, one of the biggest a charity in the United States has received from a foreign source, comes at a time when most wealthy American donors are pulling back. Only two other gifts of $100-million or more have been made so far this year, compared with 21 gifts of that size last year. Such sluggish giving is a key reason why a growing number of American charities are seeking money overseas.

At Children’s National Medical Center, the money from United Arab Emirates will pay for research and the development of new treatments designed to make pediatric surgeries more precise, less painful, and less invasive.

The gift to Children’s came about in large part because of a push from the philanthropist Joseph E. Robert Jr., who in 2000 made a $25-million gift to establish a new surgical center at the medical center.

A decade ago, Mr. Robert’s son underwent a lengthy but successful surgery at Children’s, and several years later, Mr. Robert, chairman of a global real-estate and asset-management company, invited Kurt Newman, a surgeon who had cared for his son, and other Children’s officials to come to his home. There, over breakfast, Mr. Robert asked them what it would take for the medical center to become best in the world at pediatric surgery.

“We sat down here at the house with Kurt Newman, and I asked him to think in the future tense about what surgery would look like 20 years from now,” recalls Mr. Robert. “How will genetics play into it? I said go out and get the best and the brightest. I asked them to design it.”

It took three years, but working with Mr. Robert, the medical center developed some ambitious goals and a detailed business plan to swiftly advance children’s surgeries.

The plan was to bring researchers, doctors, and other experts together to focus on four areas: developing medicines that eliminate pain, using children’s own immune systems to fight illness and prevent the need for surgery when possible, perfecting bioengineering techniques that make surgical treatments more precise, and tailoring treatments to a child’s genetic characteristics.

The price tag: at least $100-million.

Mr. Robert once again took the lead. Last year he showed the hospital’s proposal to the crown prince of Abu Dhabi, whom Mr. Robert knows from his business dealings in the United Arab Emirates.

It was not the first time the prince had heard about the medical center: For nearly 10 years, the Washington institution has treated children from the United Arab Emirates; to date, some 1,200 children from the country have traveled there for surgery or other treatment.

Soon the crown prince’s brother, Khalifa bin Zayed Al Nahyan, the president of the United Arab Emirates, was involved in talking about the hospital’s needs, and the Health Authority of Abu Dhabi, one of the country’s seven emirates, began working with the medical center on the project and agreed to provide $150-million.

The money from the United Arab Emirates has few strings attached. Children’s officials said that $60-million will be used to pay for research and programs, including hiring 125 new researchers and other employees, and $40-million will be used to improve facilities. Another $25-million will be used to create an endowment that will support a new institute focused on innovation. The final $25-million can be used for projects the hospital’s board wants to undertake.

Edwin K. Zechman, Children’s chief executive, said the gift was unusual not just for the size but also for its purpose. “It is not often that you get the resources to transform and innovate. A lot of the time you’re just focused on meeting the budget. Now we have a chance to have a global impact for kids.”

Adds Peter Holbrook, the institution’s chief medical officer: “This whole long saga started when Kurt Newman took care of Joe Robert’s son. That started a friendship that translated into Joe making his request to make things as good as possible. So this thing started with a personal connection, but it was followed by some really hard work that translates into a magnificent gift for children of the world.”