SYDNEY — Sling & Stone founder and CEO Vuki Vujasinovic is stepping down after 14 years with the Australia-based PR firm. From January 1, Sling & Stone will be led by current global head of business and 10-agency veteran James Hutchinson, who has been named CEO. Founded by Vujasinovic in 2010 to focus on startups and disruptor brands in Australia, Sling & Stone has grown to a team of more than 80 across Australia, the US, New Zealand and Singapore.