In a portfolio management how do you manage interdependency between projects

Question

I'm dealing with few projects across the site, a lot of them with interdependencies. Any tips to manage them? To communicate between the PMs and more importantly communicate plans/risks/issues across the project execution?

Answer 1

A simple tool you can use is called an N-squared chart, also called an NxN (N by N) or N^2. It’s a dependency matrix that shows not only a dependency but the direction of influence as well. By placing all the elements on the diagonal rather than just the row and column headings, you can easily see that A drives a change to B instead of just that they are somehow related by depicting the direction of influence in a clockwise manner.

 Each dependency is numbered, and the details of the dependency are contained in a separate list.