Over the past three decades much has been learned about the role and importance of psychological vulnerabilities in the context of unreliability of information obtained during police interviews. This paper reviews the current state of knowledge and explains why vulnerabilities are important. Psychological vulnerabilities are best construed as potential ‘risk factors’ rather than definitive markers of unreliability. They are important, because they may place witnesses, victims, and suspects at a disadvantage in terms of coping with the demand characteristics of the interview (and subsequent Court process) and being able to provide the police with salient, detailed, accurate, and coherent answers to questions. Early identification of relevant and pertinent vulnerabilities in the interview process helps to ensure fairness and justice. Currently, the identification of vulnerabilities is poor, and even when identified, they are not always acted upon. Nevertheless, England has taken the lead in improving the police interview process and the protection of vulnerable interviewees. More work needs to be done, but the Bradley Report recommendations represent an excellent opportunity for police and health care professionals to work together to improve justice for all. This is the key initial interface that will be vital for reducing future miscarriages of justice.