I managed a project in a company where I was the only person with experience of using formal methods (Prince 2).
The directors of the company, and the other senior staff, all took the attitude that the project was my responsibility, and if I asked for help they would give it - but otherwise I should just go away and deliver the results.
They were not interested in forming a project board, or reviewing risk registers, or even breaking it into manageable stages. It's not that they were disinterested - they just didn't "get" the reason for formal processes, as they had never used them in the past. It's not that all of their projects had been successful in the past: their management style just didn't fit with formal processes.
I capitulated and delivered the project (on time and budget and to their satisfaction, amazingly) without imposing any formal processes outside my own project team, but I felt very exposed. If I faced a similar situation again, how should I handle it?