toilet training help!

Question
Hi, I have just adopted a six month old  male miniature schnauzer from a rescue centre..he had never been toilet trained..after two weeks he will now do his number 2's outside but holds his urine until he gets back home..it doesn't matter how long a walk we take..he retains his urine until we are home and then relieves himself..why is he doing this and how can I get him to do both outside..I am using a command/praise/treats and this is working for the poop but not the pee..i would really appreciate any advice..thank you

Answer
Ever longer walks might work.  I wonder if he is afraid to urinate in front of you.  He may be afraid of bowel movements too, but be unable to hold them as long.  If you don't have a fenced yard, try tethering him outside for short periods of time.  Dogs shouldn't be left chained up outside, but there is nothing wrong with it for short periods of time when you can watch him.  if it seems to work, you can try catching him in the act and praising and treating him.  He will catch on to outside being OK.  

When you are around you need to keep a close eye on the dog. Use closed doors or gates to keep it in the same room as you are, and perhaps as I do, a short chain fastened to the computer desk. If you catch it in the act, give it a sharp ''Ah, ah, ah!'' and take it out.  If you don't catch him in the act, never punish him.