Carlisle's follow-up to the success of
Heaven on Earth was "
Runaway Horses" of
October 23 1989. The album again hit the Top Five in both, Australia and the UK, certified double platinum in both countries, but surprisingly failed to reach similar success in the US. The first release,
Leave a Light On was peaking at #11 in the US and became another Top Five smash in the UK and Australia. The song features a slide guitar solo by
George Harrison (see
Greatest Hits). The second US single, "
Summer Rain" reached #30 in Spring 1990. The song, which Carlisle noted was the most difficult song she had ever sung up to that point, peaked successfully at #6 in Australia where it has maintained popularity, and the tune saw a cover version in 2004 by the Australian group
Slinkee Minx. Whereas in the US, Carlisle's success was decreasing, her popularity remained big in Europe and Australia. In 1990, further singles from the "Runaway Horses" album were successful as well, the summer mood influenced
La Luna,a Top 20 hit in Germany and Australia, and the powerful rock hymne
(We Want) the Same Thing, another Top 10 smash in the UK.
In the late autumn of 1990, the Go-Go's reunited for a tour to support their greatest-hits album "Go Go's Greatest", including a new recording of the cover song "Cool Jerk". A notable feature of the tour was an anti-fur campaign, where the band members supported
People for the Ethical Treatment of Animals (PETA), an animal rights organization. Later in the year, Carlisle joined with
The Smithereens lead singer Pat Dinizio on his group's ballad "Blue Period."