Is going for refuge central to all Buddhist traditions? In the Triratna community, who I practice with, we see going for refuge to the three jewels as our central practice - the three jewels being the Buddha, Dharma and the Sangha. In fact the name Triratna means the three jewels. However the founder of the movement (Sangharakshita) makes the stronger claim that this is the central act of all Buddhist traditions. The Triratna movement is an explicit attempt to return to that core teaching.

However I'd really be interested in the perspectives of the different Buddhist traditions on that. Does that ring true to people in their own practices. Is going for refuge the central act of Buddhist practice?
In every single branch of Buddhism I have looked into, going for refuge is seen as the defining feature of what makes you a Buddhist. The Theravada school holds to this position, every form of East Asian Mahayana Buddhism I've read about holds this position, and Tibetan Buddhism also puts great stress on going for refuge to the point where reciting the refuge formula with Bodhichitta 100,000 times (usually combined with prostration and visualizing the refuge tree) is a central part of Tibetan Ngöndro, or foundational practice.

I think that Sangharakshita really was correct in identifying the central role of refuge in all Buddhist traditions.