Issaquah is a city in King County, Washington, United States. The population was 11,212 at the 2000 census.

Based on per capita income, one of the more reliable measures of affluence, Issaquah ranks 25th of 522 areas in the state of Washington to be ranked.

According to the Washington State Office of Financial Management, Issaquah ranked 6th of 279 eligible incorporated communities in population growth between 2000 and 2005.

Issaquah was officially incorporated on April 29, 1892.

Initially a small mining town, this town has changed noticeably both in its appearance and economic focus. Issaquah was originally developed to service the mining industry on nearby Tiger Mountain, and began as the town of Gilman, Washington. As the mining deposits neared depletion in the late 1890s, other companies started to realize Issaquah's potential to support a lucrative lumber business. These companies exported timber from Issaquah and other small, local towns to Seattle and larger, rapidly growing communities throughout western Washington. These early boom industries, however, faded into a period of relative quiet by the time of the Great Depression. The town remained fairly placid through the succeeding decades, with The Boeing Company providing the majority of employment in the area. Microsoft and other technological industries moved into Redmond, Washington and other cities in the area, and later established operations in Issaquah itself. Both Boeing and Microsoft have significantly affected Issaquah's history, cultural development, and diverse population through their active community participation and attraction of outside residents. In June 1996, Costco moved their global headquarters to Issaquah from neighboring Kirkland, Washington (thus the origin of their Kirkland Signature brand). An interesting fact: Boeing's first wooden seaplane was built by employees from Issaquah and took off from Lake Sammamish (located at the northern edge of downtown Issaquah).

Issaquah is located at 47°32′8″N, 122°2′36″W (47.535573, -122.043298),^GR1 or the south end of Lake Sammamish 17 miles east of downtown Seattle.

According to the United States Census Bureau, the city has a total area of 21.9 km² (8.4 mi²). 21.8 km² (8.4 mi²) of it is land and 0.1 km² (0.04 mi²) of it (0.35%) is water.

Issaquah is surrounded on three sides by the Issaquah Alps: Cougar Mountain on the west, Squak Mountain to the south, and Tiger Mountain to the east. To the north of Issaquah is Lake Sammamish. Cougar Mountain contains many large residential communities, while Squak and Tiger Mountains have much smaller populations. Geologists have noted the chemical and geological content of these three mountains to be much different than that of the Cascade Mountain Range, simply because they are not volcanic in origin, while the entire Cascade Range is postulated to have formed from volcanic action. They believe that these three mountains are the remains of a much older mountain range long since destroyed by earthquakes, volcanic action, and shifting plates.