After 5 yrs of working in a blue chip company, I'm considering doing a business-related Ph.D.Should I resign and do it full time for 3yrs - then what happns to my career at the end?Should I do it part-time (5yrs) and work full time?Should I even do it at all? But I'm passionate about having a Ph.D!!!

What field do you work in?What's the PHD?Will it provide better career advancing options?Can you afford to do one full time?Can you not look at options of having one sponsored by said blue chip?

Ph.D is a great degree to have. Having Dr before your name inspires respect and opens several doors. I would say do it part-time if you can. That way you remain both in the industry and academia.

Ph.D Crazy - anon's advice is spot on.