A tailor is a person who makes or alters clothing, particularly men's clothing. The Oxford English Dictionary dates the term to the thirteenth century.

Although clothing construction goes back to prehistory, there is evidence of tailor shops in Ancient Greece and Rome, as well as tailoring tools such as irons and shears. The profession of tailor in Europe became formalized in the High Middle Ages through the establishment of guilds. Tailors' guilds instituted a system of masters, journeymen, and apprentices. Guild members established rules to limit competition and establish quality standards. In 1244, members of the tailor's guild in Bologna established statutes to govern their profession and required anyone working as a tailor to join the guild.

In England, the Statute of Artificers, passed in 1563, included the profession of tailor as one of the trades that could be entered only by serving a term of apprenticeship, typically seven years.

A typical tailor shop would have a master, a foreman, several journeymen, and apprentices. The apprentices, often beginning their training as young adolescents and indentured to the master by their parents (for a fee), performed menial tasks such as cleaning, managing the fires to heat the pressing-irons, running errands, and matching fabric and trims. Apprentices were also taught the "tailor's posture", to sit cross-legged on a raised board or bench while they sewed. A tailoring establishment then generally consisted of a well-appointed room in which the master would measure customers. Cutting, sewing, buttonholes, and finishing work were performed in adjoining rooms.

In England, there were many negative associations with the profession of tailoring. Tailors were often called "snips", "bodkins", "thimbles", "shreds", "stiches" [sic], and "geese" (referring to the tailor's "goose" or iron). In William Shakespeare's plays, a tailor was variously called a "thread", a "thimble", and a "rag". By reputation, tailors were generally presumed to drink to excess and to have effeminate tendencies (likely because of the view of sewing as a woman's activity). Tailors were presumed to be physically weak and to have delicate constitutions. It was commonly asserted that their diets consisted of cabbage. In comics, they were portrayed as cuckolds or henpecked husbands. A common saying at the time was "Nine tailors make a man".

As with other artisanal trades, tailors relied on the "house of call" or "call houses", a trade club at which they could procure workmen. Sometimes, a skilled journeyman assigned by the call house would be taken on permanently by the master. Master tailors who failed to comply with laws of wages or hours could lose access to the call houses, and journeymen whose work was reported as poor could be removed from the call book. Many tailors became virtually blind from the extensive hours of stitching by hand with only candelight to illumine the work. The call for tailoring peaked in the winter, and tailors were often unemployed for several months over the summer.

During the 18th century, the profession began to shift toward large-scale and specialized production. A hierarchy of skills resulted, with the most prestigious level reserved for those who cut the cloth. "Mere sewers" ranked below the "cutters". More respect was given to those who worked in a master's workshop than those who took in piecework in their own home. Tasks grew more specialized; by the end of the century, one individual might focus solely on collars and sleeves.

The trade was one of the first in England to exhibit labor disputes, with tailors frequently on strike against lengthy working hours, low wages, and the use of laborers outside the workshop such as women and children. The strikes generally failed; some participants were imprisoned or transported to America or Australia. The unrest eventually influenced Parliament to establish rules for wages, hours, and working conditions in the tailoring industry. Tailors were one of the first trades in England to form a labor union.