nonviolent communication. It really improved my ability to communicate and understand people.

https://www.amazon.com/Nonviolent-Communication-Language-Lif...

Great post. Your reading list is excellent and I'd add Getting to Yes. I think there are some key elements you left out: (1) the concept of emotional safety and the value of brainstorming (Crucial Conversations), (2) seeing the problem as separate from the people (Getting Past No / Getting to Yes), (3) Negotiating interests, not positions (Getting to Yes).

Here are the links to the reading list (and I added Getting to Yes):

https://www.amazon.com/Difficult-Conversations-Discuss-What-...

https://www.amazon.com/Crucial-Conversations-Talking-Stakes-...

https://www.amazon.com/Nonviolent-Communication-Language-Lif...

https://www.amazon.com/Getting-Past-Negotiating-Difficult-Si...

https://www.amazon.com/Getting-Yes-Negotiating-Agreement-Wit...