45 CFR §1611.9

1. (a)When a recipient provides extended service to a client, the recipient shall execute a written retainer agreement with the client. The retainer agreement shall be executed when representation commences or as soon thereafter as is practicable. Such retainer agreement must be in a form consistent with the applicable rules of professional responsibility and prevailing practices in the recipient's service area and shall include, at a minimum, a statement identifying the legal problem for which representation is sought, and the nature of the legal services to be provided.
2. (b)No written retainer agreement is required for advice and counsel or brief service provided by the recipient to the client or for legal services provided to the client by a private attorney pursuant to 45 CFR part 1614.
3. (c)The recipient shall maintain copies of all retainer agreements generated in accordance with this section.