After the beginning of the First World War in August 1914, she was initially assigned to the Dover Patrol and was then transferred to the 8th Destroyer Flotilla.

Foresight was sent to the Mediterranean in mid-1915 and was then assigned to the Aegean Sea a year later, together with her sister ship, Forward, and remained there until the end of the war.

The engines were designed to produce a total of 16,500 indicated horsepower (12,300 kW) which was intended to give a maximum speed of 25 knots (46 km/h; 29 mph).

[2] When Foresight ran her sea trials, she reached a speed of 25.1 knots (46.5 km/h; 28.9 mph) from 14,227 ihp (10,609 kW) for eight hours.

[3] The Forward-class cruisers carried enough coal to give them a range of 3,400 nautical miles (6,300 km; 3,900 mi) at 10 knots (19 km/h; 12 mph).

[7] The ship was in the reserve of the Portsmouth Division of the Home Fleet from completion until October 1909, when she joined the 2nd Destroyer Flotilla as its leader.