Crystal Reports Combining results from multiple tables

Message

   I am trying to create a productivity report that would list the employees name on the left and then total particular tasks in columns to the right that are completed during a report user selection. I know how to do this when the data is in one table. The problem is that I want the data to come from four different tables but to show in one report. There is an employee name field in each of the four tables, though the fields containing the employee name are named something different in each table. It would look like this but continuing on to the right with additional columns for typeofworkX.tableX that is hard to show in this format

                    Typeofwork1.table1 Typeofwork2.table1 Typeofwor1.table2
Employee 1      total                                  total                     total
Employee 2      total                                  total                     total
Employee 3      total                                  total                     total
Employee 4      total                                  total                     total

My overall parameters would be employee(s) and date range. So I am guessing I need to join particular fields from the four tables and then do some sort of cross tab to total the fields by employee. Can someone direct me on how to join fields in this manner?

Thanks