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

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

General Introduction to Boundaries from Panahi Counseling:

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

Did Leonardo da Vinci paint two Mona Lisas? Where are they?

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.

Serious disappointment when the client cancels a session.

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

Why did my ex-narcissist move so fast with his new supply marriage engagement moving in, etc.?

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

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

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

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

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

Obsessing about clients outside of work hours.

Can it be true that people know your name, not your story, they’ve heard what you’ve done, but not what you’ve been through, so take their opinions of you with a grain of salt?

Off the top of my ancient head: