Informed consent requires the person to correctly understand the nature of what is offered and to be free to choose without coercion. Where there are impediments to such decision-making, then appropriate guardians or mental health laws have been provided to enhance protection. Where consent was not fully informed, an injured patient may resort to the tort of battery or negligence for remedy unless the intrusion was as a consequence of emergency treatment to an unconscious patient in the absence of next of kin. This paper reviews the UK Bolam Principle where professional standards were set by peer standards of professional conduct and the US prudent person test in which needs of a prudent patient assume priority. It concludes that there is a need to balance both the rights of patients and obligation of doctors to ensure that justice prevails. It recognises that the final standard of duty of care remains under scrutiny, and that there was a ground swell against absolute adherence to the Bolam Principle, and a need to review the circumstances of each case.