Doing a PhD after age 35 [duplicate]

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• Does age matter to get a job/postdoc? 1 answer

I have a BS degree in Environmental Engineering (closer to chemical/process engineering than civil), MBA degree where I graduated top of the class and also an MSc degree in Entrepreneurship and Marketing.

I have been working as a professional in the field of Digital and Product Marketing for the past 11 years in increasingly larger roles. I mostly worked in start-ups and I haven't been at a company where a good to great leap has happened. This frustrates me and I find myself feeling unfulfilled in my career,not having a passion. I love my field of work but just can't seem to find a good company/team where I feel accomplished, fulfilled, challenged etc.

In the past year, an idea started growing in me: doing a PhD. I love delving in a subject matter and learning all about it, reading many books, digesting conflicting opinions and compiling my findings for my own archiving fun then recruiting friends and family on the knowledge I gained.

I am almost 36. Is it too late to start a PhD program?

If I were to start and finish a PhD program, my ultimate goal would be to be in academia. Is it too late to get a position in academia by the time I finish the program, probably around age 40-41?