Tell me about a time where you were managing a program that was falling behind schedule. What would you do differently now?

In the last organization, I was allocated to a program and due to an unexpected illness of one of my team members, it was falling behind schedule. It was my responsibility to overtake that thing even though tasks were not easy to achieve. I figured out the best approach and prioritized the tasks from most important to least and began my work.

I will use my organizational skill and develop a plan of action. If in case I have this feeling that it would be very hard to achieve the result I will ask for an extension.