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Hi Steven, I'd have to agree with EGOL here - it is something that Google should have figured out - however, to some extent I think they have. For example, if I search for optimisation software here in the UK I get results for pages which are targeted to 'optimization' as well as 'optimisation'. Whilst I'd guess that the UK spelling might not be helping you in this instance, I wonder if there might also be issues in terms of your site's authority or strength which are also causing you issues. You've not said which site you're working on, but how does it stack up in terms of domain authority and page authority versus your SERP competition? It might be worth looking into that in the first instance. The other alternative would be as EGOL highlighted - target 'optimization' instead. It occurs to me that this might be worth testing - take your page as it is right now but switch out UK for US English and see if your rankings improve. As you say you could create a US targeted subfolder on your site (I'd recommend implementing hreflang to avoid duplicate content issues) and try to tackle the issue that way - however if you're site isn't authoritative enough it likely still won't rank. Hope this helps, Hannah