Forms, Updating Fields

Hello,

I have a form where there are four fields that the user selects via a drop down combo box: account number, Group, Name and Date. The entire form is linked to a table named 'Questionaire', but all of the drop down selections are sourced throw other tables and queries. At the end of the day, all of the information flows to the 'Questionaire' table, which is the DB's main table. Subsequently, there is also a subform as part of this form, but that is beyond the question here.

What I am trying to do is change my Group field to be something that automatically populated by the database and not something that the user needs to identify. For instance, when the user begins to enter his or her information into the DB, they input their name, date, and account number....once the account number is entered, i would like to have the group automatically generate and NOT be something they must choose.

The possible account number selections are driven from a different table named 'Accounts', and in this table are the fields: Decription, Group, and so forth.

What do I need to code or build in order to have the 'Group' ID automatically update when the 'Account' number is entered?


Thanks for your assistance with this.