In Demand Forecasting releases prior to R11.0, the 'Collaborative forecasting' parameter activates the 2nd customer group (Forecast Sales Group) which can then be used to display forecasts separately by Forecast Sales Group on the forecasting forms. It also enables the offline updating of forecasts using Excel (a separate spreadsheet is created for each forecast sales group).
In Demand Forecasting R11.0 and later releases, the 'Collaborative forecasting' option has been renamed "Enable Forecast sales groups", and still controls the display of forecasts separately by Forecast Sales Group on the forecasting forms, but the use of offline Excel spreadsheets to update forecasts is now always available. The only difference is that a single spreadsheet is always produced if Forecasts Sales Groups aren't enabled and can also be optionally created even when Forecast Sales Groups are enabled.
Each Forecast Sales Group can also be optionally linked to an employee, in which case the employee can only view forecasts for their Forecast Sales Group(s) on the forecasting screens.