VLOOKUP To Find And Replace For Entire Workbook?

I have a very large spreadsheet that I am using to track/analyze enterprise roles and the permissions that go along with each role. On the first sheet, I have a list of all employees (Name, Title, Department, etc) and on another sheet, I have a list of all Security Groups and Distribution Lists (with Members.) What I need to do is create a vba script that completes (1) a VLookUp using the Name column of the Employee sheet as the Criteria and then check against the first column in the Groups/Lists sheet for the matching name. If the employee's name from the Name column is found in the Group/Lists column, replace that name with the employee's Title from the Employee sheet. I then need this process to loop and continue through each column of the Groups/Lists sheet until all columns have completed. The end result should be that all names on the Groups/Lists sheet have been replaced with the corresponding Title found on the Employee sheet.