Under “agreement” in China many Chinese will understand as verbal agreement. One must remember that you are dealing with western mind set where fear of ‘loosing face’ is well imbedded in the thinking of the self respecting business man.
So if you are dealing in the first place with known and respected company / people then you can have a security of the NDA as well general business trust build without any paperwork. Not to mention that foren company have lite chance enforcing complex agreements in the local court that rule if favor of locals.
So, travel China, meet people, spend time with them, build relationship, judge character and you will be OK.
My 2 cents worth of experience.
Peter from http://www.pa-international.com.au