“[Australian] Labour had been in office for one term and our research showed that people didn’t always believe our commitments. So our advertising agency came up with the idea of the leader hand-writing a commitment in a concrete slab and then signing his name and then saying, ‘it’s no ifs, no buts A concrete commitment’. And then when all the slabs for different promises - there were a series of promises - when the slabs were all dried they were raised and they became known as the tombstones.