every dog is different. I started my 3/4 hound 1/4 collie at 14 mths as I felt he took a long time to mature. However once I did start him, he came on in leaps and bounds with his obedience where prior to this he was very iffy. Almost as tho the hunt instinct kicking in brought it all together . . . . . he was fulfilling his role in life. I am told the smaller breeds ie whippet , bedlington x's can start earlier but I have no experince with this x. All in al I think you will know when to start him - when his recall, and obedience is spot on. Good luck.