Multi-stage transmission comprises four planetary gear sets, rotatable shafts and six shift elements. Sun of first set is connected to fifth shaft which is connectable, via first clutch, to drive shaft and is couplable, via third brake, to housing. Drive shaft is connectable, via second clutch, to seventh shaft which is connectable to carrier of fourth set and ring of third set and is connectable, via third clutch, to eighth shaft which is connected to sun of second. Sixth shaft is connected to ring of first set, carrier of second set and ring of fourth set. Third shaft is connected to sun of third set and sun of fourth set and can be coupled, via first brake, to housing. Fourth shaft is connected to carrier of first set and ring of second set and is couplable, via second brake, to housing. Drive shaft is connected to carrier of third set.