What are the most difficult aspects of project management in Software Engineering?
I have been asked to provide a brief summary of the what the most difficult aspects of being a project manager of a software engineering project.  However, I have no experience of this as I'm still at University and have no "hands on" experience of project management.

I was hoping that someone on SO would be able to provide some insight based on their experience.

What are the most difficult aspects of project management in Software Engineering?
What are the most difficult aspects of project management in Software Engineering?
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I have been asked to provide a brief summary of the what the most difficult aspects of being a project manager of a software engineering project.  However, I have no experience of this as I'm still at University and have no "hands on" experience of project management.

I was hoping that someone on SO would be able to provide some insight based on their experience.

What are the most difficult aspects of project management in Software Engineering?