I worked at a humane society for 12 years and have trained MANY! One thing you need to remember to curb your frustration level is that puppy's bladders are not yet ABLE to control that flow even if they have the general idea of what to do. Be consistent is number one rule! Take the pup out one door only each time -not every door of the house-until the training is done. And be consistent with times -after a rough play session -after a meal - first thing in morning etc. All pups we had there were trained by four months old -and that's how long their bladder will take also (4 -6 months) to mature.