Bob Stack is a Deloitte Tax LLP managing director in Deloitte’s Washington national tax/international tax services group. Bob previously served as the deputy assistant secretary for international tax affairs at the US Department of Treasury. He advises Deloitte’s US clients and collaborates with Deloitte’s global member firms on international tax developments and initiatives, including those from the OECD. Email: bstack@deloitte.com; tel: +1 202 220 2100.