Estate planning presents distinctive ethical questions: advising on the law of states where you are not licensed, representing spouses jointly, working with clients of diminishing capacity, and being named as fiduciary or scrivener. The ABA Model Rules and state analogs govern; the stakes include discipline, disqualification, and malpractice.

Advising on the law of a state where you are not admitted risks UPL; Model Rule 5.5 permits certain temporary and incidental multijurisdictional work but not a systematic practice in another state.
For clients with property or domicile in other states, associate local counsel or limit the engagement scope — and document it.
Do not let a document-assembly or 'legal tech' workflow blur the line into giving legal advice without authority; unbundled and self-help services must be structured to avoid UPL.

Representing both spouses is common but is a concurrent conflict (Model Rule 1.7) requiring informed consent, ideally in writing, and a clear confidentiality understanding (joint vs. separate).
Address in the engagement letter how you will handle a secret one spouse asks you to keep from the other — the classic 'secret asset' problem.
Watch conflicts when representing a fiduciary and beneficiaries, family businesses, or multiple generations; consider whether the client is the fiduciary or the estate/trust.

Key takeaways

Respect UPL and Rule 5.5 limits on multistate practice — associate local counsel or scope the engagement.
Joint spousal representation requires informed consent and a clear confidentiality framework up front.
Follow Rule 1.14 for diminished capacity, document capacity/undue-influence observations, and heed Rule 1.8(c) on gifts and fiduciary appointments.