To create a master record, you have to specify an account group. The account group cannot be changed after you create the master record. Your system administrator, however, can change the above-mentioned account group specifications. For more information on account group specifications, see the Define account group with screen layout activity in Customizing for Accounts Receivable and Accounts Payable. For information about system configuration, see Configuring the System Using the Implementation Guide. A change in the account group specifications may be necessary if you want to add fields to the master record that were previously hidden. For instance, if you implement Materials Management after implementing Financial Accounting, you will need to have additional fields displayed in the master record.