This is where you, in a table, link your sales accounts to the different product groups and account groups. If you have indicated in your Chart of Accounts that accounting should take place per cost center, cost unit or project, then the entire account string will be linked to the product and account groups. If you have selected a "mandatory" cost center for an account, for example, you can still leave it blank here and then be forced to enter this information on the order row. You can also link product groups and customer groups to expense accounts and inventory accounts, for those who wish to have the material cost to be recorded separately on accounting orders during invoicing. In the Settings procedure in the Global Settings module, there is a setting under the Sales tab called Enter material cost of goods in the books upon invoicing. If you activate that setting, the Sales tab in the Product Groups procedure will contain two additional columns called Expense account and Inventory account. By using the Show Matrix... button in the top right corner, you can print it as a matrix.