It is currently the most watched network newscast in the United States, with an average of 2 million more than its nearest rival, NBC Nightly News.

The weeknight edition of ABC World News Tonight airs live at 6:30 p.m. in the Eastern and 5:30 p.m. in the Central Time Zones.

[11] The newly renamed ABC Evening News was hosted, in succession, by Bob Young (January 1968 to May 1968), and then by Frank Reynolds (May 1968 to December 1970), who was joined by Howard K. Smith in May 1969.

In 1975, Howard K. Smith was moved to a commentator role, and Reasoner briefly assumed sole-anchor responsibilities until he was paired with Barbara Walters, who became the first female network anchor when she joined the program on October 4, 1976.

Ratings for the nightly news broadcast declined shortly thereafter, possibly due in part to the lack of chemistry between Reasoner and Walters.

Even in areas with three full-time network affiliates, ABC stations often opted to broadcast the news program in the 6:00 p.m./5:00 p.m. timeslot to entice viewers by presenting the day's national and international news first, thus making it more likely that they would stay tuned to the station's local newscast immediately following the program (or one half-hour afterward), instead of turning to CBS or NBC.

This version was produced by WGBH, the Boston PBS station, which provided the captions and repackaged the broadcast with additional news stories – some of which were of special interest to the hearing impaired – as well as late-news developments, weather forecasts, and sports scores inserted in place of commercials.

[16] Reynolds, who was demoted when the network hired Reasoner, returned as lead anchor, reporting from ABC News' Washington, D.C. bureau.

In September 1984, the program was renamed World News Tonight with Peter Jennings to reflect its sole anchor and senior editor.

His death ended the era of the so-called "Big Three" anchors: Jennings, NBC's Tom Brokaw, and CBS's Dan Rather (the latter two had retired from their positions as the respective anchors of NBC Nightly News and the CBS Evening News within the year prior to Jennings's death).

As a tribute to its recently deceased anchor, ABC continued to introduce the broadcast as World News Tonight with Peter Jennings in the week following his death.

[clarification needed] On January 29, 2006, Woodruff and his cameraman, Doug Vogt, were injured by a road-side bomb while riding in an Iraqi military convoy.

Within a few months after Woodruff's accident, ABC News announced that Vargas was pregnant and due to give birth to her second child in late summer.

For about a month, Good Morning America co-hosts Charles Gibson and Diane Sawyer had alternated co-anchoring the newscast with Vargas.

At the time, it was unknown what ABC News planned to do until Woodruff returned to the anchor chair, which appeared not to be within the near future, and when Vargas began her maternity leave.

[18] Also starting in early 2006, the West Coast editions of World News Tonight were scaled back because Vargas anchored the broadcast on her own at the time.

Charles Gibson was then named sole anchor of the program, effectively replacing Vargas and her injured co-anchor Woodruff.

[19] Vargas cited her doctors' recommendation to cut back her schedule considerably because of her maternity leave, and her wish to spend more time with her new baby.

[23] The network chose to make the, albeit minor, change to remove "Tonight" from the title to reflect the program's expansion into the "24-hour space created by the digital world".

[28][failed verification] Gibson's final broadcast ended with a video tribute that included all of the living former U.S. Presidents, former ABC anchors, actors and actresses, singers, comedians, Mickey Mouse, Kermit the Frog, athletes, the commander of the International Space Station, competitors Couric and Williams, and was capped off by U.S. President Barack Obama.

1 network evening newscast in all major key demographics and significantly closed the ratings gap with NBC Nightly News in total viewership.

World News Tonight has broadcast from San Bernardino, Orlando, Paris, and Brussels after terrorist attacks, and from Dallas after five policemen were shot dead in July 2016.

The last time World News held the top spot was during the 1998–99 season when Peter Jennings sat at the anchor's desk, according to Nielsen.

ABC first attempted an early evening weekend newscast in July 1975, when it debuted a Saturday bulletin that was anchored by Ted Koppel and taken over by Tom Jarriel and Sylvia Chase in 1977.

Because of declining affiliate interest (in part because of the proliferation of 24-hour cable news channels such as CNN) and low viewership, ABC discontinued the late-night weekend reports in September 1991.

The program, which had affiliate clearance problems and was thus unsuccessful in terms of ratings, ended in 1975, replaced by the network's inaugural Saturday newscast (see above).

[48] Some ABC affiliates air the Saturday and Sunday editions of World News Tonight at 6:00 p.m. Eastern and Pacific Time (5:00 p.m. Central and Mountain)‍—‌one half-hour earlier than the weekday broadcasts.

The weekend editions of World News Tonight may periodically be abbreviated or preempted outright due to sports telecasts that overrun into its timeslot or occasionally air immediately following the program (the latter preemption situation commonly affects stations in the Pacific and Mountain Time Zones); this is particularly common during fall, as the Saturday broadcast does not air at all from September through mid December due to ABC's college football coverage and during the winter and spring, when the Sunday broadcast is sometimes delayed or preempted due to overruns of the network's NBA telecasts.

Similarly, cable companies in Canada simulcast the program with most airing from either Seattle-based KOMO, Boston-based WCVB, or Detroit-based WXYZ which operate as timeshift channels.

[51][52] In Hong Kong, the program was broadcast live on TVB Pearl daily at 07:30 until 08:00 HKT until May 31, 2009, when it was replaced by NBC Nightly News.