The Zurich West Prison (Gefängnis Zürich West, GZW) is a part of the Police and Justice Centre (Polizei- und Justizzentrum, PJZ) which is currently being built on the grounds of Zurich’s former freight terminal.

After its inauguration, the Zurich West Prison will house persons under provisional arrest (124 places) and in pre-trial detention (117 new places).

During provisional arrest (also known as police detention), the prosecution authorities have a maximum of 48 hours to make the necessary assessments in order to either confirm or rebut the suspicions and other reasons for incarceration. If there are no reasons for incarceration (or not anymore), the person under provisional arrest is released. Otherwise, a request for a pre-trial detention order is submitted to the coercive measures court (in German) which then has 48 hours to adjudicate on the matter.

If the coercive measures court approves the request for pre-trial detention, the incarcerated person is moved to the prison’s pre-trial detention block or to another pre-trial prison of the Zurich Pre-Trial Prisons (Untersuchungsgefängnisse Zürich, UGZ).

After the inauguration of the Zurich West Prison, it will supersede the provisional police prison on the grounds of Zurich's former military barracks, and the enforcement of provisional arrests will no longer be handled by the police, but by the Zurich Pre-Trial Prisons.