The phrase "a complex business that" is correct and usable in written English.
You can use it when describing a situation, organization, or process that involves multiple intricate elements or factors.
Example: "The project turned out to be a complex business that required extensive planning and collaboration among various departments."
Alternatives: "a complicated matter that" or "an intricate issue that".
Agriculture distribution is a complex business that involves many sets of hands, health officials said.
But applying it to human behaviour is a complex business that involves huge problems of selection.
"Food is a complex business that requires sourcing the best ingredients, making hundreds of meals, and delivering those meals quickly and efficiently" Biyani admits.
The company is an example of a complex business that can face significant challenges acquiring and retaining customers, as well as one that faces an existential threat from Amazon.
Historian David Carter remarks in his book about the Stonewall riots that the bar itself was a complex business that represented a community center, an opportunity for the Mafia to blackmail its own customers, a home, and a place of "exploitation and degradation".
The design of a clinical trial is a complex business that requires careful consideration of several factors, with one of the most crucial being the assessment of the targeted improvement in the primary outcome measure, which is also one of the principal determinants of sample size.
As the Guardian found during its rural development project in Katine, north-east Uganda, doing good development aid – as opposed to emergency aid – is a slow and complex business that involves multiple players.
The humiliations of Brexit continue to rain down upon us, but it took Donald Trump to remind the British government that negotiating trade deals is a long, painful and necessarily complex business that would only be made harder by Theresa May's plan for leaving the European Union.
David Cameron said he was delighted with the appointment, while Heywood said he brought "a strong private sector performance culture and long experience of running complex businesses that require the full range of commercial, specialist, digital and delivery skills".
Running a business is a complex job that involves finance, sales, communications, intellectual property, product creation, organizational culture, marketing, systemization, technology deployment, branding and the list goes on.
Mining projects are complex businesses that demand constant risk assessment.
