UKH

So... My wife and I are hopefully adopting a child in the relatively near future and trying to get everything together that we need, a changing bag being one obvious thing. As the age of the child we will adopt is uncertain and wanting to get something that could do for a variety of situations and environments as well as last a long time, has anyone found a good backpack that does for walking but also doubles as a changing bag? Thinking good back system, hip and sternum straps, bottle pockets as well as other pockets on outside for quick access to the myriad of things that are necessary.

Any decent rucksack with side pockets should do, best if you can get an old one that has a flap-lid with a zip pocket in it, as that gives you an extra pocket

All it needs is a folding change mat, space for bottles/milk powder (if he/she is that young, wipes), a couple of small Tupperware type boxes for small foods, nappies, cloths, bibs, change of clothes, some small zipseal bags (very large sandwich bags), cuddly toy. Don't overthink it. I'd say 25 litre would be more than adequate.

Best wishes and good luck with the adoption!

Congratulations on the adoption! Have a look at Little Life, we had a toddler carrier - or just a sling for a baby (Connecta) - but basically we just bought a 40 litre rucksack which we used for babies / picnics and now my son uses for scouts.

Right I have recent experience on this. We bought a bag that wasn't big enough and have now gone for the smaller of the Patagonia Cragsmith bags (32l), because we like the back opening. The slot for your climbing shoes is perfect for a jojo baby changing mat to slot in and the fully opening back is much easier as you can see at a glance what you have in the bag. If you have a wriggling child you don't have time to explore the contents of a top opening bag. 

Thought the bag was quite expensive btw but it seems well made and fits under the pram. Back opening is key, any back opener would be good I think. 

Thanks everyone. All useful considerations. It feels very easy to go all in on getting the "perfect" option for everything and always good to be reminded that isn't necessarily an option.

I don't remember having a changing bag bought for the purpose, but babies' stuff does take up a fair bit of space. 

Top-opening bags would, indeed, be a bad idea, but besides that, go big with lots of pockets.