Nonviolent Communication is a communication process which is based on the principles of nonviolence and compassion as the natural state of human beings. It can be used to reduce the triggers in our communication, resolve conflict (including within ourselves) and increase our empathy and connection with ourselves and others. 'NVC is founded on language and communication skills that strengthen our ability to remain human.' -"Nonviolent Communication: A Language of Life" by Marshall Rosenberg, PhD.
NVC was developed by Marshall Rosenberg beginning in the 1960s. It recognizes the valid, universal human needs underneath our behaviour. By becoming aware of our own needs and the needs of the other party, we are better situated to find a strategy that meets the needs of all involved. Marshall says our needs are never in conflict; it is our strategies (the action that we take to attempt to meet our needs) that clash. You can use NVC even if the other person is non-verbal, disengaged, dead or otherwise not speaking to you. It's a powerful paradigm shift that can revolutionize your relationships and empower you to take responsibility for meeting your needs regardless of your situation.
'The objective of Nonviolent Communication is not to change people and their behavior in order to get our way: it is to establish relationships based on honesty and empathy, which will eventually fulfill everyone's needs.' -Marshall Rosenberg
NVC can be used in families, workplaces, educational settings, prisons, boardrooms and more. There are several books available, including the one mentioned above, and you can attend in-person and online trainings all over the world. Look for a certified trainer to make sure your facilitator has a good understanding of NVC. Many of Marshall's talks are available on YouTube. Marshall died in 2015 but his voice and teachings live on.
You can learn more at the Centre for Nonviolent Communication. https://www.cnvc.org/
Helpful tools include a printed list of Feelings and Needs (available at the CNVC website or included in any training), Feelings and Needs cards or magnets for the fridge, and a printed sheet of the OFNR process: Observation, Feeling, Need, Request. OFNR are the four steps to learn to communicate using NVC. It sounds something like 'When I see/hear/imagine/remember ...., I feel .... because I need ... Would you be willing to ...?'