In U.S. civil trial practice, the same legal professional, an attorney, or firm of legal professionals, usually handles a case from first client contact through trial and often appeals (if any) as well.
But, in English law, the roles of attorneys in the U.S. are filled by more than one kind of legal professional and there is a distinction between barristers, who are legal professionals who mostly handle trial practice, and solicitors, who are legal professionals who do other kinds of legal work. I am generally familiar with the routes by which one enters each profession.
It isn't clear to me, however, how the lines are drawn between the two professions in the context of civil litigation.
For example, suppose that you have a medium sized business (e.g. 100 employees and several business locations with no in house counsel) with a regular outside solicitor or firm of solicitors that it employs.
Suppose that business gets into a serious business dispute with another business, e.g. a joint venture gone bad with related accounting and trademark issues involving hundreds of thousands to million of pounds in controversy economically. (The example is from a case I handled in the U.S. allowing me to compare it, but any serious civil dispute could do. I limit the question to serious civil disputes because I understand that solicitors can handle civil litigation in some minor civil litigation.)
At what point in time is there a transition from a solicitor to a barrister?
When would a client start with a barrister in the first place?
What kind of legal professional (barrister or solicitor) would represent a client in an arbitration or mediation proceeding in which no court case has been opened?
Would a medium sized business in the example above that gets into lawsuits once every year or two typically have a regular barrister (or firm of barristers) that they would use, or would this choice usually be made on a case by case basis?
Also, please feel to correct any of my assumptions if they are incorrect.