[1] It is a problem play about the moral dilemmas created by limited medical resources, and the conflicts between the demands of private medicine as a business and a vocation.

Sir Colenso must choose which patient he will save: a kindly, altruistic, poor medical colleague, or a young artist who is extremely gifted, but an amoral, very unpleasant womaniser and bigamist.

Sir Colenso has also fallen in love with the young and vivacious Jennifer Dubedat, which makes it even harder for him to be clear about his motives for choosing who shall live.

As a founding member of the Fabian movement in 1884, Shaw – a school drop-out who had used the British Library to achieve a massive self-education programme in his 20s and was active in local politics in the deprived London area of St Pancras – was a passionate critic of the huge disparities between the wealthy and the poor, and his unique combination of prodigious intellect and panoramic knowledge meant that he was seldom intimidated in his mission for fairness and truth (a substantial part of the Preface, however, is given over to a glittering harangue against vivisection).

At the time of this play he was a highly successful dramatist, with works such as Man and Superman and Major Barbara enjoying international acclaim.

The two men met in 1905, and engaged in a long series of robust discussions, involving at one point a challenge from the medical audience that they had "too many patients on our hands already".

[4] The preface mentions that there is another dilemma: poor doctors are easily tempted to perform costly but useless (and in the best case harmless) operations or treatments on their patients for personal gain.

This was reportedly inspired by the behaviour of a prominent Ear Nose and Throat specialist in London who had developed a simple and almost harmless operation to remove the uvula, which did no benefit to his patients but made the surgeon a great deal of money.

A film adaptation of the play, with the same title, was made in 1958, directed by Anthony Asquith, starring Leslie Caron and Dirk Bogarde.