There is a Projects_Form and Employees_Form.

In the Employees_Form, there is a multi-select field named Related_Offices.

Each Projects_Form Record contains a multi-select look-up to the Employees_Form.

I would like a field in the Projects_Form called "Total_Number_of_Related_Offices", that automatically displays the number of unique related offices for that project.

For Example:

Form: Projects_Form

Record: Project One

Lookup:          Bob - Human Resources,  Mobile Division, Tech Support

                        Janet -Human Resources, Tech Support

                        Alex - Manufacturing

Total_Number_of_Related_Offices: 4