The legal invoicing process typically begins when lawyers and staff log their billable and non-billable time working on a client file. At the appropriate time for billing—perhaps on a monthly basis, when the legal matter comes to an end, or some other milestone event—the lawyer responsible for the file will review time entries, revising or removing entries when necessary. Finally, a staff member will prepare an invoice detailing the work done and the amount owing, then send it to the client.