If you are talking of house-training, then you can try around 8 weeks, but most puppies have no bladder or bowel control until about 12 weeks old. Positive re-enforcement works. Smacking your puppy and/or rubbing his face in his pee/poop does not work and it is cruel! You have to go outside with tiny treats in your pocket and your pup on a leash, stand out in the middle of the yard and ignore him until he does something. Then Immediately give him a treat and praise. Accidents will stil happen in the house for quite a while, that's just a fact of being a puppy parent. So just be patient and consistent.

I'm going to disagree with Fembot on this one. I've started training puppies for HOUSE TRAINING as soon as their eyes were open and they were able to stand, walk and FOLLOW their Mom Dog out side. I CHEAT! I use Mom Dog to help (she does most of the work actually!) They willingly follow her outside, she licks them to stimulate them to go, and when they do I PRAISE them for doing it. I've done this about 5 times with different breeds and it's actually worked every single time. By the time the pups were ready to be place at 10 to 12 weeks...they were pretty much 100% clear on the concept of going potty outside AS LONG AS THEIR NEW HUMANS were making the trips out...available! As for puppies who do not get the benefit of staying with their Mom and siblings the full optimum time (10 to 12 weeks) I'll have to disagree with PART of the statement that accidents will happen in the house. They WILL happen IF the humans are not 100% on their toes, or if the puppy is not either watched when loose in the house, not crated, or not baby gated in a safe, easy to clean area. I've never had a puppy have an accident IF I WAS WATCHING THEM PROPERLY...it's a lot of work, but it can be done...it just depends on exactly how far you are willing to go...to set the puppy or dog up for success. I have to give some points to Fembot however, because she clearly shares that negative corrections and punishment is NOT GOING TO TRAIN YOUR PUPPY...POSITIVE REINFORCEMENT IS THE BEST WAY TO TRAIN and get what you want...a house trained dog! ANYONE willing to help spread this good news deserves a TREAT every day of the week! For more "advanced" training....sit, stay, come, lay down...you can start this at 8 weeks (or once they can move well)...we do anyway by simply calling the puppy to come to us! Focused training for Sit, Lay down, and such need the student to be ABLE to focus. Eight weeks to twelve is ok to start as long as you keep in mind...the puppy cannot focus more than maybe 1 to 2 minutes at a pop right now...after 12 weeks...it starts to build up to about 3 to 5 minutes. NEVER push training time too far...it sours the animal and they will be less responsive...always end on a big positive success then quit for a while. You CAN do several training times...asking for a sit throughout the day...but don't expect a puppy of 3 or 4 months to be as able as one 6 to 8 months of age...it's not likely to happen! Make it FUN!

As soon as you bring them home. A good breeder will have started the process for you.

The day you bring them home, establish yourself as the Alpha right away. Be consistent with your training, puppies need to know what is expected of them. When they need to be corrected do it immediately, firmly but with love. Treats are another great way to train and encourage them to listen to you. Lots of love and attention gives them security. Potty training can be tricky sometimes. If your puppy just can't hold it all night there are disposable doggie diapers for the young ones.