Thanks for the reply! Maybe an example will help. I'm trying to find the overall staff minutes per day rather than the patient's minutes if you will...

STAFF, SERVICE_DATE, PATIENT, START_TIME, END_TIME, ELAPSED_MINUTES (PATIENT_MINS), STAFF_MINS

SUZY STAFF, 06/16/11, JOHNNY, 1000, 1030, 30--for staff_mins would count this as 30

SUZY STAFF, 06/16/11, DAVID, 1030, 1100, 30--for staff_mins would count this as 30

SUZY STAFF, 06/16/11, JACKSON, 1100, 1200, 60--overlap

SUZY STAFF, 06/16/11, MADDY, 1100, 1200, 60--overlap

SUZY STAFF, 06/16/11, KEVIN, 1115, 1200, 45--overlap

SUZY STAFF, 06/16/11, SARAH, 1100, 1200, 60--overlap

SUZY STAFF, 06/16/11, JUDY, 1300, 1330, 30--for staff_mins would count this as 30

The overall staff minutes that I would want to see for this staff on this day would be 150. Does that help?