In September 2019, Bill Gates presented Prime Minister Narendra Modi of India with an award on behalf of his philanthropic organization, the Gates Foundation, for the Indian leader’s work on improving sanitation.

An uproar followed.

Three Nobel Peace Prize laureates wrote to Mr. Gates, arguing that Mr. Modi, who was given the award on the sidelines of the United Nations General Assembly in New York, did not deserve the recognition because democratic and human rights had eroded under his rule. “This is particularly troubling to us, as the stated mission of your foundation is to preserve life and fight inequity,” the laureates wrote.

The outrage did little to deter Mr. Gates and Mr. Modi, who have developed an unusually warm and high-profile relationship in the past decade.

They have met several times, and Mr. Gates has been nothing but complimentary of Mr. Modi. Last year, just before a national election, Mr. Gates sat down with the prime minister for an extended televised exchange that Mr. Modi used to burnish his image as a tech-savvy leader.

The relationship between Mr. Gates and Mr. Modi, according to observers, former foundation employees and critics, yields benefits for both men. Mr. Gates is set to visit India in the coming week, his third visit in three years, and will meet with government leaders and others to discuss India’s innovations and progress.

“This trip will give me a chance to see what’s working, what’s changing and what’s next — for India and the foundation,” Mr. Gates wrote on GatesNotes, his personal blog.