Model Rule 1.5 places limits on law firm billing practices. Specifically, it states that a "lawyer's fees shall be reasonable." This same standard is applied to attorney billing across the United States.

The practice of law firms overbilling clients via exorbitant document review fees has become a familiar industry norm. However, with the advent of legal process outsourcing, it is questionable whether such practices, even if the industry norm, continue to be "reasonable." Proceeding with "business as usual" may no longer be a viable option for lawyers, who must adapt with the times.