Tritium retention in TFTR and JET shows striking similarities and contrasts. In TFTR, 5g of tritium were injected into circular plasmas over a 3.5 year period, mostly by neutral beam injection. In JET, 35g were injected into divertor plasmas over a 6 month campaign, mostly by gas puffing. In TFTR the bumper limiter provided a large source of eroded carbon and a major part of tritium was co-deposited on the limiter and vessel wall. Only a small area of the codeposit flaked off.