Paul Brock, a former public relations consultant, radio news broadcaster, movie producer and Democratic National Committee communications official who in 1975 was one of the principal organizers of the National Association of Black Journalists, died March 14 at his home in Upper Marlboro, Md. He was 89.

The cause was complications from diabetes, said his wife, Virgenia L. Embrey-Brock.

One of his earliest jobs in journalism came in 1968 when Mr. Brock became news director at the public radio station WETA-FM in Arlington, Va., for which he hosted a weekly nighttime news program called “The Potter’s House.”

In 1971, he joined Howard University’s commercial radio start-up WHUR-FM as news director and focused on covering stories about the growing political turmoil around the country, federal trials of anti-Vietnam War activists, the political and social movement of Black-pride activists, and the occupation protests of the American Indian Movement.

Around that time, Mr. Brock helped found the Washington Association of Black Journalists and served as its first president. By the mid-1970s, Mr. Brock and television journalists Maureen Bunyan and Max Robinson began a campaign to unify the various Black journalists associations from different cities into a national organization, which became known as the NABJ.

Mr. Brock, who by then was working as deputy director of communications for the DNC, developed an extensive media contact list and wrote letters inviting Black journalists to Washington to attend an organizing meeting in December 1975. The date was selected because many of the reporters were already scheduled to be in D.C. to cover a gathering of Black municipal officials from across the country.

“Paul was crucial to the organization,” Bunyan said. “Even though he wasn’t working as a journalist at the time, he gave his time and energy to helping us, and I’m not sure if we could have started without him.”

The NABJ began with 44 members and with Mr. Brock as founding executive director. In ensuing years, he rarely missed the group’s annual conference, once taking a train from Washington to the convention in New Orleans when his doctor restricted him from flying on a plane after a surgery.

The association, which has grown to a membership of more than 4,000 media professionals and journalism students, provides professional training, promotes diversity in newsrooms and scrutinizes media outlets’ coverage of minority communities.

Mr. Brock worked for more than a dozen organizations during his career. He was named senior vice president of American Urban Radio Networks in 1977. A couple of years later, he became a senior fellow for public affairs at Howard’s Institute for the Study of Educational Policy, where he wrote a widely used law school primer on the 1978 Supreme Court affirmative-action case Regents of the University of California v. Bakke.

He also held brief jobs as director for public information and communications for the NAACP and handled publicity and distribution for the TV program “Tony Brown’s Journal.” Mr. Brock moved to Hollywood in 1980 to help start a film production company, Past America, which made historical docudramas.

Paul Hillery Brock was born in Washington on Feb. 10, 1932. He was raised by his mother and stepfather, both of whom ran a delicatessen.

Mr. Brock graduated in 1950 from Armstrong High School and briefly studied pharmacology at Howard before leaving in 1951 to join the Air Force. Trained as a radio operator, he got his first job in journalism as editor of the newspaper at Griffiss Air Force Base in Rome, N.Y.

In the early 1990s, Mr. Brock returned to the Washington area and ran a communications and public affairs consulting firm as well as a film production company. He also volunteered with programs to mentor aspiring journalists.

His first marriage, to Joan Roberts, ended in divorce. In addition to Embrey-Brock, his wife of 20 years, survivors include four children from his first marriage, Michael Brock of New York, Paula Shelley Rodgers of Frederick, Md., Christopher Brock of Washington and Lisa Brock of Los Angeles; four grandchildren; and 10 great-grandchildren.