From the Benchmade website:
Gold Class – Our Gold Class clearly sets the new standard of what is possible in premium knife manufacturing. It’s quite simply the best of the best.

Blue Class – Our Blue Class represents the heart of everything that is Benchmade. These USA made products are designed and built for the individual who appreciates the difference that a high-quality cutting tool can make.

Black Class – Our Black Class products are designed, developed and tested for extreme duty. They are the preferred cutting tools for Law Enforcement, Public Safety and Elite Military Troops around the globe.

Red Class – Our Red Class offers “best in class” value. These edged tools possess the same Benchmade mindset of leading innovation, modern materials and quality manufacturing.

From everything I’ve read during my research, all Benchmade knives EXCEPT the Red Class are made here in the USA.  The Red Class knives are manufactured in China.  That’s not to say that they aren’t good quality, in fact I’ve read very good reviews and stories about several of these Red Class knives.  Personally, I try to stick to knives made in here in the USA but I’m not a fanatic about it, I do own several from other countries.

Take a look around our site for more information on specific Folding Knives we like. There is also an article I wrote on the Benchmade folding knife here.