What are some signs that a therapist may have poor boundaries with their clients?

Sense of competition with persons who are important in the client’s life.

Struggling with fantasies of deeper connections with clients, whether sexual or parental or other intense or intimate relationships beyond psychotherapy.

Serious disappointment when the client cancels a session.

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These items can happen fleetingly, briefly, in any therapy, but if they’re frequent, it’s definitely time for the therapist to get some good, solid supervision/consultation.

Session-expressed curiosities about client details not relevant to the therapy.

Eager anticipation (or anxious anticipation) of the next session in ways that distract.

Has anyone ever made you take off your shirt?

Routinely going over the time limit with certain patients, compromising the time for the next client.

General Introduction to Boundaries from Panahi Counseling:

Obsessing about clients outside of work hours.

Is Andrew Tate wanting to volunteer for the IDF to fight terrorism a way to avoid justice by the courts who have charged him with human trafficking?

Disclosing feelings, fantasies, and experiences to the client in ways not related to the work the client is engaged in.

Off the top of my ancient head:

Frequent phoning or texting of clients to “check up on them and make sure they’re OK.”

How can I get the lead guitar removed from a song so I can play the lead Guitar parts myself and have the rest of the band's music playing? Is there ought to be a website or company who can do this?

Failing to mention the client in supervision/consultation, out of fear the supervisor/consultant will advise return to ordinary healthy boundaries.