For almost three decades beginning in 1936, many African-American travelers relied on a booklet to help them decide where they could comfortably eat, sleep, buy gas, find a tailor or beauty parlor, shop on a honeymoon to Niagara Falls, or go out at night. In 1949, when the guide was 80 pages, there were five recommended hotels in Atlanta. In Cheyenne, Wyo., the Barbeque Inn was the place to stay.

A Harlem postal employee and civic leader named Victor H. Green conceived the guide in response to one too many accounts of humiliation or violence where discrimination continued to hold strong. These were facts of life not only in the Jim Crow South, but in all parts of the country, where black travelers never knew where they would be welcome. Over time its full title — “The Negro Motorist Green Book: An International Travel Guide” — became abbreviated, simply, as the “Green Book.” Those who needed to know about it knew about it. To much of the rest of America it was invisible, and by 1964, when the last edition was published, it slipped through the cracks into history.

Until he met a friend’s elderly father-in-law at a funeral a few years ago, the Atlanta writer Calvin Alexander Ramsey had never heard of the guide. But he knew firsthand the reason it existed. During his family trips between Roxboro, N.C., and Baltimore, “we packed a big lunch so my parents didn’t have to worry about having to stop somewhere that might not serve us,” recalled Mr. Ramsey, who is now 60.

He is among the writers, artists, academics and curators returning a spotlight to the guide and its author, emblematic as it was of a period when black Americans — especially professionals, salesmen, entertainers and athletes — were increasingly on the move for work, play and family visits.

In addition to hotels, the guide often pointed them to “tourist homes,” privates residences made available by their African-American owners. Mr. Ramsey has written a play, “The Green Book,” about just such a home, in Jefferson City, Mo., where a black military officer and his wife and a Jewish Holocaust survivor all spend the night just before W. E. B. DuBois is scheduled to deliver a speech in town. The play will inaugurate a staged-reading series on Sept. 15 at the restored Lincoln Theater in Washington, itself once a fixture of that city’s “black Broadway” on U Street.

Historians of travel have recognized that the great American road trip — seen as an ultimate sign of freedom — was not that free for many Americans, including those who had to worry about “sunset laws” in towns where black visitors had to be out by day’s end.

Lonnie Bunch, director of the Smithsonian’s National Museum of African American History and Culture, a co-sponsor of “The Green Book” play reading, said the presence of the guide into the 1960s pointed out that at the same time people were countering segregation with sit-ins, the need to cope with everyday life remained.

He added: “The ‘Green Book’ tried to provide a tool to deal with those situations. It also allowed families to protect their children, to help them ward off those horrible points at which they might be thrown out or not permitted to sit somewhere. It was both a defensive and a proactive mechanism.”

Although Victor Green’s initial edition only encompassed metropolitan New York, the “Green Book” soon expanded to Bermuda (white dinner jackets were recommended for gentlemen), Mexico and Canada. The 15,000 copies Green eventually printed each year were sold as a marketing tool not just to black-owned businesses but to the white marketplace, implying that it made good economic sense to take advantage of the growing affluence and mobility of African Americans. Esso stations, unusual in franchising to African Americans, were a popular place to pick one up.

Green wrote in his book’s introduction, adding, “There will be a day sometime in the near future when this guide will not have to be published. That is when we as a race will have equal opportunities and privileges in the United States.”

The Civil Rights Act was passed in 1964, and Mr. Green ceased publication.