I was contacted by a headhunter. After a few telephone interviews and a trip to London I was offered the chance to take a 3 hour exam. I was offered a job immediately thereafter.

Phone screen with a director-level employee, ~90min computer-based assessment in their office, then two more meetings with director-level staff. Each step was 1-2 weeks apart, with feedback coming anywhere from hours after a meeting to a week later. Ultimately was told they wanted someone with a different background/experience, which made the process feel like a waste of my time and theirs. Everyone I spoke with seemed very friendly and candid, but clearly their process could be improved.