A bit of research on Barclays, with what you want to do, and how you are going to do it (describe your job role).
Answered - Test Analyst (Current Employee) - Manchester
You should check current Barclays Purpose and Values - Respect, Integrity, Service, Excellence and Stewardship. Questions are related to service - great and difficult time examples.
Answered - Business Manager (Current Employee) - Sutton, Greater London
Learn about the company (basic) learn the values yet they are up everywhere. Learn about the role itself and how you can relate to the position.
Answered - Private Banking Executive (Current Employee) - Canary Wharf, Greater London
My interview for Barclays was conducted online. I was given a series of questions and had to record answers and then send them off the the recruitment team. If I was to repeat my interview at Barclays I wouldn't try too hard to prepare specific answers
Answered - Essential Banker (Current Employee) - Stafford
Read around the person who is inteviewing you , everyone likes there horn to be blown.
Answered - Solutions Architect (Former Employee) - Canary Wharf