For the underwriting executive role - it started with a 30 min phone call centered around the barclays values and ethic's. You had to give work example's showing those values 'respect', 'ethical', 'flexible etc. You would obtain the barclays values template from the barclays recruitment department anyway before the phone interview take place. It's just the case, structuring you work experiences around it.
Once pass, you will be invited for a face to face interview. The recruiter will speak to you of the date and venue it will take place and documentation to bring. Most importantly, they will attach about 4 key points where the interview will test you on. Again, you will have to give work of life examples on how you conducted this. It very much involve the STAR technique so would advise people to learn that and apply it for interviews. The interview will take place for an hour and you would have one person asking the questions and another taking notes. Around about 2 working day, they will give you a call whether you have passed or not.
This was my experience of those two interviews, could be different to you lot as you may have applied completely different jobs.
Have you ever had less than £2.00 in your account
Casual business clothing for example a black pencil skirt, a shirt and a blazer
A bit of research on Barclays, with what you want to do, and how you are going to do it (describe your job role).