New York AO154 Substitution of Attorney is a legal form used to appoint a different attorney to represent a party in a case. It is used when an attorney is no longer able to represent the party in the case, either due to death, illness, or other circumstances. This form is completed by the party replacing the attorney and is filed with the court. There are two types of New York AO154 Substitution of Attorney forms: one for criminal cases and one for civil cases. The form must be signed by both the party and the new attorney.