Horse trading, in its literal sense, is the buying and selling ofhorses, also called "horse dealing". Due to the difficulties in evaluating the merits of a horse offered for sale, the sale of horses offered great opportunities for dishonesty, leading to use of the termhorse trading (orhorsetrading) as a widespreadmetaphor for complexbargaining or other transactions, such as politicalvote trading. It was expected that horse sellers would capitalize on these opportunities and so those who dealt in horses gained a reputation for underhanded business practices.

TheTea Horse Road orChamadao (simplified Chinese:茶马道;traditional Chinese:茶馬道), now generally referred to as theAncient Tea Horse Road orChamagudao (simplified Chinese:茶马古道;traditional Chinese:茶馬古道) was a network of caravan paths winding through the mountains ofSichuan,Yunnan andTibet inSouthwest China.^[1] This was also a tea trade route.There are numerous surviving archaeological and monumental elements, including trails, bridges, way stations, market towns, palaces, staging posts, shrines and temples along the route.^[2]

As standards for ethical business declined in the United States in theGilded Age, the activities of horse traders came increasingly to be seen as the natural and, in part, desirable product of a competitive market rather than as symptoms of moral depravity. In an 1893New York Times editorial criticizing a proposed law to make it illegal for a newspaper to falsely state its circulation figures, the author declared that "if the lying were stopped by law, the business of horse trading would come to an end, and the country taverns and groceries in the Winter season would be deprived even of the limited eventfulness which they now enjoy".^[3]

Reflecting this attitude, the termhorse trading was widely adopted as a way to describe what might be seen as unethical business practices in a more positive light. It is likely the 1898 publication ofEdward Noyes Westcott'sDavid Harum – whose title character saw all business through the lens of horse trading – played a key role in this.

In a further development of meaning,horse trading has come to refer specifically to politicalvote trading. This is now the most common sense of the term, largely displacing the older term,logrolling.

In some languages political bargaining is known as "cow trading" (German:Kuhhandel,Swedish:Kohandel,Finnish:Lehmänkauppa). InSweden, the May 1933 agreement between theSwedish Social Democratic Party and theSwedish Farmers' League which came to shape the economic politics of Sweden during the 20th century, known as theNordic Model, was called "the cow trade"^[4]

• Aaya Ram Gaya Ram
• Aisle (political term)
• Conscience vote
• Crossing the floor
• Keep the bastards honest
• Party switching
• Transformism, flexible centrist coalition government by unification of the extreme left and right
• Whip (politics), in UK politics voting against the party line is known as "defying the whip"

  The dictionary definition ofhorsetrading at Wiktionary