In terms preferred by economists, a situation defined by a principal-agent problem (such as you hiring a doctor or car mechanic who gets to both define your problem and figure out what to charge you for fixing it) was replaced by a much simpler employment relationship: would-be hustlers found themselves being turned into professional, generalist managers.

FORBES: Entrepreneurs are the New Labor: Part I

Not only does the author clearly define the problem, he proposes some unique solutions and ideas to train your dog quicker and keep both you, your carpet and Fido happy.

CNN: Site-Seer: Fetching an obedient dog from the Web