1. Initial HR phone call 2. Two rounds of technical phone screen First was with a Sr. Staff Engineer (who was my mentor for the summer internship): questions were all related to the background of my intern tasks. Challenging and required attention to detail. Second was with a Sr. Member of Technical Staff: general algorithm and coding questions. 3. I did very well in the first phone interview and pretty well in the second. Mentor later told me I was one of the best candidates he's ever interviewed, and I'm glad I was able to work with him during my internship at Palo Alto headquarter.