The phrase "secure their interests" is correct and usable in written English.
You can use this phrase when you want to talk about taking the necessary steps to protect someone or something from possible harm or damage. For example: "The company took steps to secure their interests by investing in secure software."
The wealthy hire lobbyists; they try to secure their interests with campaign donations.
They either conclude that we don't care about their interests, or that we aren't competent enough to secure their interests.
"If the Americans coöperate and let the Baath Party back, they can secure their interests in Iraq at a very cheap price," he said.
As the seven-year conflict draws to a close, each participant in the war, Syrian and non-Syrian, is trying to secure their interests, many of which run through Idlib.
Is it plausible that Russia, China or America would risk armed conflict to secure their interests in such circumstances?
"The fact of the matter is that there are groups inside both Iran and the United States who can only secure their interests if hostile relations continue," he says.
Private sector financiers, naturally, seek to secure their interest in space equipment.
Many increasingly see no possible positive outcome of their neighbor's bloody conflict, no clear solution for securing their interests in the meanwhile.
They, too, began to think in terms of putting Constantinople under Western control as the only means of securing their interest in Byzantine trade.
In his dealings with Edward III, Robert blamed his border magnates for the escalating attacks on the English zones but regardless of this the Scots retained the recaptured lands, which were often portioned out among minor lords, so securing their interest in preventing English re-possession.
The KGB, the CIA and MI6 were all active in the country as they sought to secure their countries' interests.
