The mission of the museum is to collect, preserve and interpret the clocks and objects relating to the Willard clockmakers who made clocks in Grafton, Lexington, Roxbury and Boston, Massachusetts between 1766 and 1870, and to interpret life in central Massachusetts between 1750 and 1825.

Nestled in the rolling hills of Central Massachusetts, Willard House* is Grafton's oldest building, constructed in 1718 by Joseph Willard in what was then known as the Indian settlement of Hassanamisco. Four of Joseph's grandsons - Benjamin, Simon, Ephraim and Aaron Willard - would become America's preeminent 19th century clockmakers, making their first clocks in 1766 in their small Grafton workshop. In 1802, Simon Willard obtained a patent for his Improved Timepiece, or "banjo" clock. Today the banjo is considered to be one of the most significant styles of early 19th century American timepieces.

The museum opened in 1971 and features the world's largest collection of Willard clocks. The collection is displayed in period room settings in the 1718 Joseph Willard homestead, the 1766 Benjamin Willard Clock Manufactory and three modern galleries, and also includes: more than 90 Willard clocks; Willard family portraits and furnishings; Colonial, Federal and Empire period furniture; antique Oriental rugs; 19th century women's costumes; 18th century American and English pewter; Victorian dolls and doll furniture; military and hunting weapons; Nipmuc Indian artifacts; and original documents signed by Thomas Jefferson and James Madison.