The talks followed clashes at an anti-government protest in Tbilisi and a brief military mutiny outside the city last week, which had led to concerns that the unrest could spread through the rest of the country.
In a televised address after the meeting, Saakashvili said: "We agreed on the fact that it is a step forward, that the dialogue should be continued. I have no illusions that we will reach agreement on all issues."
He said he had offered to work jointly with the opposition on a new electoral code and constitutional reforms, and to increase their participation in state institutions.
Despite the month-long protests, which have seen up to 60,000 people take to Tbilisi's streets, Saakashvili has refused to step down until his term ends in 2013.
Zurabishvili, a former foreign minister, was joined at the talks by Irakli Alasania, a former envoy to the UN; Levan Gachechiladze, an ex-presidential candidate; and Kakha Shartava, leader of the National Forum party.
They argue that in addition to domestic issues, Saakashvili walked into an unsuccessful war with Russia last year over the breakaway region of South Osettia that Georgia could not possibly have won.
The government's offer of reforms is testing the unity of more than a dozen parties who have taken part in the demonstrations.
Some say it is too late to negotiate with the president, pointing to previous unfulfilled promises and arguing that they will only discuss Saakashvili's departure from power.
Other, such as Alasania, have urged urging patience and have said that dialogue is the "only way out of the current political crisis".
The meeting between Saakashvili and the opposition came on the same day as an official opening ceremony for Nato military exercises in Georgia.
The drills have angered Moscow which sees the area as falling within its traditional sphere of influence.
Vladimir Putin, Russia's prime minister, said on Sunday that the army exercises were a tacit sign of Western support for Saakashvili's government.
"Against this background they [Nato] decided to carry out the war games," Putin said in an interview with Japanese media.
"Of course, this cannot be seen as anything other than support for the ruling regime. And why support such a regime?"
Russia has in recent months expressed its opposition to what it calls Nato's expansion into Georgia and Ukraine, two former Soviet republics whose governments have expressed their desire to join the military alliance.