Look for the purple 'Professional Standards Authority Accredited Register' logo - if you are looking for a therapist then the 'Professional Standards Authority Accredited Register' logo is a good indication that the therapist has undertaken rigorous and in depth training and works in accordance with their registered codes of practice and code of ethics.
The Professional Standards Authority for Health and Social Care promotes the health, safety and wellbeing of patients, service users and the public by raising standards of regulation and voluntary registration of people working in health and care. It is an independent body, accountable to the UK Parliament.
The main purpose of the Accredited Registers scheme is to protect the public and raise professional standards. The Authority sets high standards for organisations holding registers and Accredited Registers require practitioners to meet high standards of personal behaviour, technical competence and where applicable, business practice. This helps protect the public.
More information can be found here: https://www.professionalstandards.org.uk/…/about-accre…/faqs
The above image shows my Professional Accredited Membership of the National Counselling and Psychotherapists Society and my PSA Accredited Register membership.