We have every reason to celebrate the framework agreement with Iran. It exemplifies the best of President Obama’s foreign policy, namely, engaging adversaries. Remember when candidate Obama’s argument for engagement during campaign 2008 was ridiculed by Hillary Clinton, among many others? Now Obama has two major engagement successes to crow about, leaving behind those who are quick to criticize the deals with Cuba and Iran as anything from foolish to treasonous.

To reach this point after more than 35 years when other administrations have either failed to cut a deal or refused to try is nothing short of extraordinary. And in the case of Iran, the nuclear agreement comes at a crucial moment, not merely in terms of Iran’s nuclear-weapon potential but more broadly with respect to the chaotic shape of Middle East politics.

John Limbert was a political officer in the U.S. embassy in Tehran when the nightmare hostage crisis unfolded in 1979. Out of his captivity has come a seminal guide, “Negotiating with Iran: Wrestling the Ghosts of History (2009),” which reflects his deep background in Persian studies and his commitment to dialogue and mutual understanding. His book examines several cases of crisis in Iran and then offers a number of guidelines to successfully negotiating with the Iranians. At a time when we are hearing loud criticisms of the nuclear deal and efforts by Congress, and Israel, to undermine it, we should pay attention to what experts like Limbert have to say.

Limbert proposes 14 negotiating lessons. I have selected seven, and added one of my own. Comparing the lessons with the framework just concluded allows us to see how effectively the two countries’ diplomats worked together.

Avoid legalisms; seek solutions based on “mutually agreeable standards” that Iran can claim as a victory. Having two MIT scientists who knew of one another discuss technicalities was a key to successful talks. That allowed many details of an accord to focus on science, not politics. As for claiming victory, while Secretary of State John Kerry could cite major concessions by Iran, Foreign Minister Mohammad Javad Zarif could boast that Iran will keep its centrifuges and nuclear enrichment program, its major nuclear research site at Fordo, and some of its uranium stockpile.

“Be aware of Iran’s historical greatness” and past grievances based on humiliations by foreign powers. President Obama, in an interview with Thomas Friedman of the New York Times and elsewhere, has shown his attentiveness to Iran’s history and culture. He has pointed to the Ayatollah Ali Khamenei’s mention of Iran’s unhappy history with the United States and has made respectful comments about Iran’s greatness and right to acknowledgment as a major regional power.

Throughout the years of talks with Iran, its leaders have above all else demanded “respect.” The nuclear negotiations have provided that.

Clarify lines of authority: be sure to talk with the right people, but also present a common U.S. position. This was a challenging lesson to follow inasmuch as the ayatollah deliberately kept in the background without committing himself to the outcome. Nevertheless, the “right people” were evidently at the table and were able to craft an agreement that the ayatollah did not negate.

Understand Iranian interests. Obviously, removing the sanctions was essential to a deal, but not at any price. Iran’s insistence on keeping fuel rods at home and not shipped to Russia was essential face-saving, and U.S. negotiators did not allow that position to halt the talks. Likewise on the centrifuges issue: The U.S. negotiated down their number (from about 19,000 to 6,000), but Iran still has some 5,000 allowed to operate according to CIA director John O. Brennan.

Do not assume the Iranians are illogical, uncompromising, untrustworthy, duplicitous. U.S. negotiators clearly did not. Hopefully, they kept in mind that many Iranians view Americans the same way.

Ignore hostile rhetoric and grandstanding; be businesslike and professional — and be willing to stay the course.

Remember that there were successful U.S.-Iran talks in the past, for example in 2001-2002 over Afghanistan following the fall of the Taliban.

Be ever-conscious of the politics of a deal. This is why the “optics” of the deal are so important, with each side having a different narrative of the deal’s strengths so as to make it more attractive domestically.

The nuclear deal with Iran, if it holds, could potentially open a new era in U.S.-Middle East relations. Though the Saudis, the Israelis, and some other supposed friends will object, a cooperative U.S.-Iran relationship is a critical piece in the overall puzzle to find a path to something resembling stability. We can see the outlines of cooperation with Iran in Iraq and Afghanistan, where Washington and Tehran have common interests. Simply put, Iran’s leaders feel threatened by ISIS, al-Qaida, and the Taliban.

To be sure, there are also places — Yemen, Israel/Palestine, Libya, and Syria — where the U.S. and Iran are at odds. But if the nuclear deal can move forward, the agenda of cooperation may expand and violence-by-proxy may greatly reduce. For the United States, an end to one-sided relationships in the Middle East would be a blessing, with positive ramifications for Israel and others seeking stability in the region.

Mel Gurtov is professor emeritus of Political Science at Portland State University and editor-in-chief of Asian Perspective. He wrote this for PeaceVoice.