The trust which runs mental healthcare in Sussex and parts of Kent has been told to improve.
A report by the Care Quality Commission (CQC) has found that the Sussex Partnership NHS Foundation Trust "requires improvement" following an inspection in January.
Concerns were raised about cleanliness and a failure to draw up a plan to tackle the high suicide rate in Sussex.
The trust said improvements had been made and some areas were well rated.
Colm Donaghy, who is the trust's chief executive, said: "It's difficult when there's criticism of leadership. You shouldn't take it personally, but you should take it really seriously."
Dr Paul Lelliott, CQC's deputy chief inspector of hospitals, said there had been "considerable variation" in the quality of the services provided by the trust.
He said: "While most community-based services were good, some areas of care in learning disability and older people's inpatient services were inadequate.
"These services require urgent attention to bring them up to acceptable standards."