Meanwhile, the Iranian leadership has its own set of challenges ahead.

Using the Internet to provide local news can present its own set of challenges.

It comprises a set of activities and challenges over a 24 hour period.

The coming year was going to present a new set of challenges.

"You start over every year with a new set of challenges," he said.

When soldiers return, managers face a new set of challenges.

As you well know, our nation faces a daunting set of challenges.

To begin to do so, she laid down a set of challenges for both leaders.

Here they will face a completely different set of challenges.

Life at the top, she understood, presented a different set of challenges.