Very casual. Was interviewed by the team manager (Lead Mechanical Engineer) where he/she spent most of the interview explaining the duties of the role. Asked very high level questions about my education, extra-curriculars, hobbies, and interests in the job. It was very clear that the interviewer wanted someone who was considering a long-term position with WSP, and for that reason the emphasis was on determining if I was well-rounded vs. technically-sound.