Use these principles to make your Sprint Zero a success :
So how to do a Sprint 0 in a smart way ? Use these principles :
A length of more than 1 week for Sprint Zero is way too long
Spending half of Sprint Zero on training and teambuilding is only nearly enough
To do more than strictly needed to start the first sprint is too much
The outcome of Sprint Zero is a jump start for Sprint One.
See Xebia blog for full blogpost.