Citywest is the name of a business park and neighbouring golf resort just north and northwest of Saggart in County Dublin, Ireland. The nearest major town is Tallaght. The business park has developed a small residential population in recent years. The River Camac passes north of the business park, and two of its tributaries pass through it.

Originally a landed property known as Tassaggart, located north of Saggart village, well to the west of Tallaght, and largely south of what became the Naas dual carriageway (now the M7 / N7), the Citywest concept was launched by Irish construction firm Davy Holdings, who began building the business park in the early 1990s, and Jim Mansfield, who managed the hotel and leisure aspects of the project. They then named the modern developments Citywest.

A substantial golf course, the Citywest and Hibernian Golf Club, now simply Citywest Golf Resort, was laid-out. The Citywest Hotel, the largest in Ireland, with over 1,700 rooms, was built adjacent to this. The hotel, golf resort and related developments were placed in receivership in mid-2010.

Following the opening of the original business park the N82 National road joining the N81 to the Naas dual carriageway was re-routed through the campus. It previously passed through the village of Saggart itself.

Several major businesses moved to the business park, notably Eircom, mobile operator Meteor, and Independent News and Media, and branch offices of Xilinx, Unilever, Pfizer, SAP and Roche. In mid-2012, Independent News and Media began a move out of Citywest, to Talbot Street in Dublin's centre.

The Luas Line A1 Citywest extension from Belgard to Saggart was officially opened on Fortunestown Lane, Saggart on 2 July 2011 by the Minister for transport Leo Varadkar. The following stops were constructed on the line - Fettercairn, Cheeverstown, Citywest Campus, Fortunestown and Saggart. A park and ride facility was constructed at the Cheeverstown stop.