The Sammamish people (Lushootseed: sc̓ababš) are a Lushootseed-speaking Southern Coast Salish people. They are indigenous to the Sammamish River Valley in central King County, Washington. The Sammamish speak Lushootseed, a Coast Salish language which was historically spoken across most of Puget Sound, although its usage today is mostly reserved for cultural and ceremonial practices.

Historically, the Sammamish were a distinct tribe. The 1855 Treaty of Point Elliott assigned the Sammamish people to Tulalip Reservation, and today many of their descendants are citizens of the Tulalip Tribes of Washington. Other Sammamish people moved to other reservations in the region, and today their descendants are citizens of the Muckleshoot Indian Tribe, Snoqualmie Indian Tribe, and Suquamish Indian Tribe of the Port Madison Reservation.

The historical extent of Sammamish territory ranges from the northern head of Lake Washington to Issaquah Creek at the south of Lake Sammamish, where they have hunted, fished, and gathered for over 10,000 years. The Sammamish had several villages along the length of the river, with the largest being at ƛ̕ax̌ʷadis, what is now Kenmore. The Sammamish were historically a warlike, but impoverished people, and were closely allied with their neighbors, the Duwamish and the Snoqualmie. Traditional Sammamish society revolved around their two lakes, Lake Washington and Lake Sammamish, more than the Sammamish River which connects the two.

In the early 19th century, the Sammamish were one of the first peoples of Puget Sound to come into contact with the traders from the Hudson's Bay Company. During this period, the Sammamish participated in several wars, such as the 1855 Puget Sound War and the 1856 Battle of Seattle, as well as raiding other tribes. In 1855, the Sammamish attended, but did not sign, the Treaty of Point Elliott. Despite this, they were removed from their land and sent to the Tulalip Reservation, where many Sammamish descendants live today. Other Sammamish continued to live in their traditional homeland along the Sammamish River but later moved to neighboring reservations.

The name "Sammamish" is an anglicization of their Lushootseed endonym, sc̓ababš, also spelled sc̓əpabš.

The etymology of the name sc̓ababš is disputed among historians and linguists, and there are several possible etymologies. The name is derived from a root word and the suffix =abš, meaning "people." According to linguist and anthropologist T.T. Waterman, the name means "meander dwellers." According to historian and writer David Buerge, the name might derive from the word sc̓ap, meaning "willow," which would mean their name translates to "willow people."

The first American settlers also called the Sammamish various names such as "Squak", "Simump", and "Squowh." These names are anglicizations of the Lushootseed word sqawx̌, the name for Issaquah Creek and the location of a Sammamish village.

The Sammamish are a Southern Coast Salish people. They were historically closely related to and allied with their immediate neighbors, who today constitute the Snoqualmie and the various subgroups of the Duwamish people, such as the təbɬtubixʷ, the Juanita Creek people. Because of these ties, early American settlers often believed that the Sammamish were a subgroup of the Duwamish, or that the Duwamish were a subgroup of the Sammamish. However, the Sammamish were a completely sovereign and autonomous group from their Duwamish neighbors. Some historians have continued to classify the Sammamish as a Duwamish subgroup.