how important is it to buy the newest edition textbooks?

[Lola1233]

new editions are ridiculously expensive -- can I get away with just buying and older edition (esp if it was within 3 years)? And why the heck does a textbook have 8 editions published within a 20 year period anyway?!

[citychild]

I would make sure to get the go-ahead from your professor first. Most that I have asked have approved...

[MsDarjeeling]

It depends on how the book will be used in the class and what has changed in the new edition.  Asking the professor is a good idea.  You can also see if your campus library or bookstore has both versions and review them to see.  If say only one or two chapters are drastically different you can probably photocopy those.  If the whole book has been completely overhauled then the new one will be better.