The people inside each team are always talking to each other, never to a manager (he/she is also part of the team, no hierarchy, no exceptions). It is of essential importance that people in the team trust each other. When we are a team, we grow together.
Project management through different practices explores the teams and their trust and researches the elements of highly effective teams. This is very often found in Scrum and Agile practices.
The book "Tactical Management in Complexity" researches and helps improving the professional relationships in the company and as well as project management, it influences trust. In this context, please refer to the segment of the book explaining the phases of research dedicated on team's effectiveness:
To close the discussion on teams and trust, I would like to suggest an essential reading by Table Group Inc. referring to the five dysfunctions of a team: https://www.tablegroup.com/download/the-five-dysfunctions-model-and-summary/. For me, trust and our team are teaching us how much attention as professionals we need to pay to becoming part of a team, a trustworthy individual contributing to the final goal. It turns out, we all need to start with trust.