list all files in a folder and all files in all its subfolders

I’d like to be able to list all files in a folder that contains both files and files in subfolders.
Is it difficult?
Something like this:
repeat for every folder inside the main folder
add every file to myList
return 1 list including every single file in the chosen folder

Give this a shot

set theFolder to choose folder
tell application "Finder"
	set theFiles to every file of entire contents of theFolder
end tell

Brlliant! Thanks and so short