Representation in an immigration case does not begin when money changes hands, and it does not begin at the first meeting. It begins when a notice of appearance is filed and accepted. Before USCIS that document is Form G-28, the Notice of Entry of Appearance as Attorney or Accredited Representative; in immigration court and before the Board of Immigration Appeals it is Form EOIR-28 or EOIR-27. Until one of those is on file, the agency treats you as unrepresented, whatever your fee agreement says, and it will address you directly.
The form is short, which is part of why people sign it without reading the back. A careful reader looks at four things before signing: who is named as the representative, what the person's basis for appearing is, which specific matter the appearance covers, and which boxes control where the government sends paper. Each of those has consequences that surface months later, usually at the worst moment.
What each signature actually promises
The representative's signature is a statement to the government, made under the rules of professional conduct, that the person is either an attorney in good standing with a state bar or a representative accredited through the Department of Justice, which oversees the recognition and accreditation program and the immigration courts themselves. Your signature does something different. It authorizes that person to receive information about your case, to speak for you, and to accept notices on your behalf. It also consents to the agency dealing with the representative instead of you, which is the practical effect people notice first.
Note the scope line. A G-28 is filed for a matter, not for a lifetime. A representative who filed for your I-130 petition is not automatically on the record for the adjustment application, the work permit, or a later naturalization case, and each filing generally needs its own form. Immigration court appearances are narrower still: an EOIR-28 can be limited, in some circumstances, to a particular hearing or filing rather than the whole proceeding, and the difference should be stated in the fee agreement rather than assumed.
Where the mail goes after it is filed
Once the form is accepted, correspondence routing changes. Requests for evidence, interview notices, receipt and approval notices, and hearing notices go to the representative's address of record. The G-28 lets you choose whether original notices and secure documents go to you or to your representative, and that choice is worth making deliberately. Many people want notices sent to counsel and the actual card or document sent to their own home. A careful reader confirms that the address printed on the form is the office that will really open the envelope, not a former suite number.
Two habits protect you afterward. First, create a USCIS online account and link your receipt numbers, so that case status and uploaded notices are visible to you directly rather than only through the office. Second, keep your own address current with the agency. Being represented does not suspend the obligation to report a change of address, and a notice mailed to a stale address is still a notice.
When the person you hired stops answering
Silence is a problem precisely because the mail is going somewhere you cannot see. Start by writing rather than calling, so there is a dated record: an email and a letter to the address on the G-28, stating what you need and by when. Ask specifically for a copy of the complete file, which is yours, and for the receipt numbers of everything filed. If nothing comes back, the state bar's client assistance program handles attorney complaints, and the Executive Office for Immigration Review maintains a disciplinary process for practitioners who appear before it.
Withdrawing or replacing without losing a date
Deadlines do not pause while representation changes, so sequence matters. Before USCIS, a new representative simply files a fresh G-28, which supersedes the earlier one; the prior representative may also file a withdrawal, but your filing dates and receipt numbers are unaffected. In immigration court the change is formal: the new attorney files an EOIR-28, and the outgoing one files a motion to withdraw, which the judge grants or denies. Never miss a hearing because a substitution is pending. Appear, tell the judge what is happening, and ask for a continuance on the record.
Keep copies of every notice of appearance you sign, with the date, and check the receipt notices when they arrive to confirm the representative's name appears where you expect it. That one habit tells you, at a glance, who the government currently believes is speaking for you.