Upon applying to S&P online for an internship with their communications department, I received a phone call from human resources with preliminary questions concerning my education and background. About an hour later, I received another call from the same person offering me an in-person interview with the head of the press office at their Canary Wharf location.
On the day of the interview, I arrived about 15 minutes early. Instead of waiting that entire time, my interviewer came out early and was very friendly. We talked for about 15 or 20 minutes while he looked through my CV and asked me a series of questions about why I wanted the job, what my background was, and what I thought my strengths were. He then went to find a higher up, who came in and sat down with me individually as well. They were both very personable people and the interview never seemed contrived or awkward. The office was extremely nice and the environment was professional yet surprisingly calm.
I received a phone call a few days later from the same person at HR. He gave me great reviews on my interview, actually quoting a couple of the things the interviewers had said about the interview. He then gave me the interview statistics of how many people applied (over a hundred) and how many people were called in for an interview (less than 10). So I didn't get the position, but the experience was extremely positive and also provided me with helpful practice and feedback.