In 1998, Reagan's proposal finally started to take physical shape with the first piece of the ISS launching into space.
Since then, a major construction program has been ongoing some 350 kilometres above the earth to complete the station.
Although it won't be fully assembled until 2010, the ISS is already the largest human-made object ever to orbit the earth.
But, while the flashy space shuttle launches to the ISS make for good TV, often the actual purpose of the mission gets overlooked.
All the scientific jargon aside, the main reason the ISS was built was so that scientists could observe how humans live and work in space during extended durations.
Scientists say that knowledge will help them with future missions to the moon and even Mars -- which takes six to nine months travel time each way.
For example, on his upcoming six-month stay aboard the ISS, Canadian astronaut Robert Thirsk will take medicine as part of a study to see how his bones react to the weightless environment.
"For a long-duration space flight the physical toll is primarily on the muscles and the bones that support our bodies," Thirsk told CTV.ca in a recent interview.
"The muscles of the back, legs and then the bones in the vertebrae, in our hips, in our shins and in our heels, those will all waste away."
The medication, commonly used to help people with osteoporosis, will hopefully help minimize his bone loss.
That research will help scientists who are trying to figure out how to send astronauts on long-distance flights without their bones deteriorating.
Scientists are also using the ISS to study the impacts of long-term confinement and isolation on the astronauts.
Thirsk leaves for the ISS this May as the crew on the station will grow from three to six people for the first time.
The upcoming space shuttle Discovery flight, scheduled to blast off Sunday, is bringing up a US$300 million set of solar wing panels.
Those panels will help power the ISS as the crew expands from three to six. During Thirsk's stay, there will also be a number of shuttle missions to the ISS.
In June, the first shuttle crew to visit the six astronauts will include Canadian astronaut Julie Payette. Her trip will mark the first time two Canadians have been in space simultaneously.
It'll also be the first time every single partner of the ISS project will be represented in space.
"When we're all up in the hatch, the seven of us from the shuttle will join the six from the station for a total of 13 people, which will be historical," Payette told CTV.ca in a recent interview. "There's never been that many people in space at the same time -- ever."
In 1999, Payette became the first Canadian to participate in an ISS assembly mission and to board the space station.
At that time, the station was very small with only two modules and nobody permanently inside.
"Since then, the space program has grown 10 times over," Payette said.
During her upcoming 16-day trip, Payette and her crewmembers will be responsible for five spacewalks to install the remaining components of Kibo, a Japanese-built experiment facility.
Payette will serve as a mission specialist responsible for the station systems and will also be operating the Canadarm.