Is humility an important leader's characteristic?

Of course I do agree with you. Humility is the quality of being humble - Being humble is a great thing and strength and you can interact with people better than arrogance for sure.

I recommend the webinar "9 Habits of Effective Team Building for Project Managers" by Bruce Harpham, which addresses this topic and provides tips on how to engage team members in a project

After survive to multiple managemet styles along the years applied for my managers I found that servant leadership is the most effective. Inside the model there is not an attribute related to humility. On the other side, humility is related to recognize the proper strenght and weekness. And that is always important to improve yourself.

100% agree. Humility is also the capability to fairly understand what is happening around you: somebody with a smarter idea, some very bad (or very good) project decision you took. When it is time to 'speak-up' or when it is better to listen to better understand what is going on...I think it is not by chance that between the brightest mind, artist, engineers etc...I had the luck to know, most of them were amazingly humble

I agree that Humility is an important characteristic in a leader. I believe it allows him/her to complete a full 360 degree look at a process/problem. The focus is on the issue/task not the leader or the people.. Those around the leader can feel that and it allows them space to step up and grow.. If you haven't already, you may want to read the book "Good to Great" by Jim Collins, it has some data around successful leaders and how humility plays a part..

thanks Bala for your comment. Elaborating your last consideration we can affirm that Humility helps to "turn on" a synergistic process on behalf of the project.
Do you agree with this my affirmation?

Thanks Rami for your comment. your comment point out about an important theme: in the communication the attitude through we transmit the message... is a part of the message!

I am with you on this Fosco.

This is true, it is always about the pitch, tone, body language so usually when you are arrogant while talking to people, they might understand 40% of what you said because 60% of their mind is occupied thinking how much they do not like the attitude.