Make an selection in map and pass the selection to an geoproccing tool

Hello I wonder how this issue could be resolved:

- I make an selection in map

- Want to take the selection result and pass it over to an geoproccesing tool for futher analyse.

Or:

Make an selection and run an workflow tool where I can add som new queries on the result as COUNT, SUM etc etc

Best regards

Jan-Henrik Nilsen