A thatcher is a craftsperson who builds roofs using dried plant materials like straw, reeds, or rushes. Instead of using shingles or tiles, a thatcher bundles and layers these materials so tightly that rain runs off without leaking through.

Thatched roofs have been used for thousands of years in many parts of the world, from English cottages to African huts to Japanese farmhouses. The work requires real skill: a thatcher must know how to trim and arrange the materials at just the right angle, how to secure them so wind won't tear them loose, and how to create a roof that might last 30 years or more.

Though most modern buildings use other roofing materials, thatching remains a respected traditional craft in places like England and Ireland, where historic thatched cottages are preserved and maintained. A well-made thatched roof has a distinctive thick, rounded appearance and provides excellent insulation, keeping buildings cool in summer and warm in winter.

The word can also refer to someone who removes thatch (dead grass and plant material) from lawns, though this is a completely different meaning of the term.