The President plays a unique and indispensable role in the chain of command.

For example, never have so many feminists praised the indispensable role of fathers.

Quality plays an indispensable role in helping companies achieve their social responsibility objectives.

I have said often and cannot say enough that journalists played an indispensable role.

They have a fundamental and indispensable role to play in keeping our nation safe and helping us to understand other countries.

But I think the council performs a useful if not indispensable role in inventing a lot of things for economic common sense.

We believe that human rights defenders play an indispensable role in society.

But perhaps you forget your own father's indispensable role.

This is because each molecule plays an indispensable role in biology.

That is where you, the teacher, play an indispensable role.