Note that the classification of firms throughout this course is subjective and fairly arbitrary in places.
For example, there are firms in the Silver Circle section that, for whatever reason, are not usually associated with this label, even though they are equally as well-regarded (if not better regarded) than some of the other Silver Circle firms. There are also firms in the mid-market section that are top ranked for specific services or in specific industries. And many of them do high profile international work, as well as national work. Regional firms (meaning firms with offices in different regions of the UK) may also have a few (or dozens of) offices abroad.
In other words, there's no objective criteria that can be used to neatly categorise all firms, so don't take these classifications as a true indication of which firms are "better" than others.
Note that we have focused primarily on firms that offer at least a few training contracts in the UK each year (we have generally omitted firms that only offer two or three). We have also omitted leading firms headquartered in the US or other jurisdictions that don't recruit trainee solicitors in the UK (e.g. Cravath, Swaine & Moore and Quinn Emanuel Urquhart & Sullivan), although many of these do recruit qualified lawyers for their London offices.