Mrs oldgrump is recovering from an achilles op and has been told to get walking in boots to support her ankle. Any suggestions about what lightweight boot to buy?

I have apair of Salomon which I think are the dogs and weren't that expensive, but there are so many variables, you really need to try them on. Outdoors shops will have a walking ramp to allow giving them a bit of a tryout.

Ive got a pair of Inov8's which are good, very grippy. Not hugely supportive though but comfortable.
As BBSB said above, try some out.

Personally I'd say that "ankle support" is mostly a myth. The only boots which give ankle support are ski boots, and hey you can even twist your ankle wearing those. Lots of boots LOOK like they might support, but they don't stop you turning an ankle, and they lead to poorer posture and weaker joints.

If it hurts don't do it. Boots won't fix your tendon.

Yes, I'm a skeptic and after years of heavy duty walking boots, have come to the conclusion (like may others) that lightweight shoes are mostly the way to go – unless you really need the boots for protection.

Got to be down to fit and comfort. I have some Brasher Supalite which are expensive and light and not all that supportive/stiff, but the Karrimor cheapies I have would be much better if I was wanting specific ankle support, but maybe a proper orthapedic brace is what's really needed.

Cheers for the thoughts.

Berghaus Explorer GTX in leather – super light, super grippy, 100% waterproof, very comfy and pretty cheap.