The phrase "a highly complex issue" is correct and usable in written English.
You can use it when discussing topics that involve multiple layers of difficulty or intricacy, often in academic, professional, or analytical contexts.
Example: "The debate surrounding climate change is a highly complex issue that requires careful consideration of various scientific, economic, and social factors."
Alternatives: "a very complicated matter" or "an extremely intricate problem."
Homelessness is a highly complex issue, and our priority is to ensure that those individuals affected get the right support.
What my insight has shown me is that whether or not we should be part of the EU is a highly complex issue.
Hans van Ginkel, UN under-secretary-general and rector of the university, said: "This is a highly complex issue, with global organisations already overwhelmed by the demands of conventionally recognised refugees.
A spokeswoman for the Wellcome Trust said climate change and health was "a highly complex issue which we take seriously in our decisions and on which we engage with policymakers, researchers and the businesses in which we invest".
9.36am: Nick Clegg, the deputy prime minister and Lib Dem leader (left), has been speaking out about yesterday's vote: This was a very difficult vote, especially for Liberal Democrats, on a highly complex issue.
Cavendish believes it to be a highly complex issue and agrees that major factors to consider are dependency and control; "Dependence works both ways - financial for many prisoners, particularly those who don't have family ties, as well as emotional".
Some observers argued that the main stumbling block was not Jerusalem but the Palestinian refugees and that for historic and emotional reasons it was difficult for Arafat to declare an end of the conflict with less than a full resolution of that highly complex issue.
Specialization of the clinics to the clinics of the DS is highly complex issue and it requires many system solutions.
As mentioned above the issue of how much a particular state owes to another state is a highly complex unresolved issue.
Aboriginal hunts of marine mammals are a highly complex ethical issue.
"In the handful of cases where FIRB has intervened, these cases involved transactions of national significance and highly complex issues, where specific concerns unique to a particular asset have arisen.
