Where to start - grouping etc

[smods]

Hi All,

I have a sheet which I log entries onto that I capture various information on.

I then have a summary sheet which totals up the information by week number using countif's and sumif's giving a summary for the week.

How would I go about setting up grouping on the summary page so I can also display a breakdown by department per week?

I hope I have explained this weel enough

Regards

Chris