An international giant, Sidley Austin - where alumni include, inter alia, Michelle Obama and her husband - is traditionally a structured finance-heavy firm.
Currently running at about 100 lawyers in London (out of 1,800 worldwide) the firm is of a reasonable size. Securitisation has always been a big deal here.
Despite some diversification, most of its work remains in the corporate and banking spheres, and whilst it does a bit of property and IP, realistically there won't be much room for those without a strong financial background. As one trainee noted in the RollOnFriday Firm of the Year survey, "Everyone [is] expected to do a corporate and finance seat", which "can be restrictive, although, on the other hand, what do people expect?"
Sidley Austin is a pretty anglicised firm and has had an office in London since 1974. But don't hope for too relaxed an approach to the long-hours culture; this is still a US firm (an NQ writes that they have "a 'concealed firearms policy' and a 'how to escape from your office if 911 happens again' emergency pack in our desks"). And you don't get paid the rates on the right by knocking off at 18:00 every evening, so expect to work as hard here as at any major UK firm. So while some say that "weekends are respected, on the whole", others say that there is "no work life balance". Although at least the "Halloween party and roof-top summer Hawaiian luau are epic".
Chances of joining the partnership from the inside are pretty slim. Still, you could do some damage with the salary in the meantime.