5 months - 1 Yr
 

 
This stage is probably the most difficult to deal with in the Jindo.  Remember that puppy that would follow you everywhere and lived for whatever you pleased?  That puppy has now turned in the canine equivalent of a teenage.  Rebellious and  independent.
 

1.        Hormones kick in...Spay/Neuter
 

If you don't plan on breeding your dog, I strongly recommend that you consider spaying and neutering.   Hormones will exacerbate the potential problems you run across at this age such as aggression towards other dogs - even with dogs that they have lived with since 8 weeks of age.

2.        Enroll in obedience school
 

Up until this age, positive reinforcement should have been used.  With the advent of the rebellious teenage years, though, Jindos usually require a firmer hand.  They should be introduced to negative reinforcement when they do something they know is prohibited.

I recommend that people enroll in a good obedience school so that they may learn how to correctly dole out negative reinforcement without inadvertantly crossing into abuse.