Just seen that Tesco online are now offering kefir. Great! Have been finding this very difficult to source locally. I've ordered a pot just to test whether they'll actually deliver, since this is a new product for them and these things are sometimes a bit slow to get distributed nationally. If customers don't buy it they won't keep stocking it, though, so fingers crossed... I've also ordered direct from: http://www.nourishkefir.co.uk/ who were excellent in quick, well-packed, keep-fresh delivery but you have to order rather a large amount and although the expiry date on mine was about 5 weeks, I wouldn't want to start my next MAF batch with kefir near its expiry date. Pity it's not more widely available in shops locally.