Designed as an Army Co-operation aircraft the Lysander would serve in France and Belgium during the early months of the Second World War. After suffering heavy losses during the Battle of France the type was phased out of front line service. Thanks to its short take-off and landing performance the Westland Lysander would serve with the Special Operations Executive and is best remembered in this role.

The Air Ministry were looking to replace the aircraft used for co-operation and liaison, which at the time was the Hawker Hector, so in 1934 issued specification A.39/34. This required an aircraft which had short take-off and landing requirements and could be used for a variety of roles including reconnaissance and bombing.

Westland submitted their design during June 1935 and a contract for two prototypes, designated P.8 by Westland, was awarded with the prototype undergoing taxying trials on the 10th June 1936 before its maiden flight on the 15th June 1936. This was followed by an appearance, before the month was out, at the SBAC Display at Hatfield. The new aircraft was then sent to Martlesham Heath and the Aircraft and Armament Experimental Establishment, which was based there, for handling evaluation on the 24th July 1936. The second Lysander prototype made its maiden flight on the 11th December 1936, two months after one hundred and forty four production aircraft had been ordered, and like the first this was sent to the A&AEE at Martlesham Heath. During 1938 the second prototype was to undergo tropical trials and was dispatched to No. 5 Squadron.

It was to be No. 16 Squadron, Old Sarum, who were the first to take delivery of the new plane, having their Hawker Audux replaced during June 1938. The Lysander Mk I, which was powered by the 890-hp Bristol Mercury XII engine, had a top speed of 219 mph, range of 600 miles with a service ceiling of 26,000 ft. Armament was four 0.303-in machine-guns and 500lb bombs. When war broke out in September 1939 a total of seven Westland Lysander squadrons were in service and that month also saw the introduction of the Lysander Mk II. With the entry into service of the Mk II a number of the Mk Is were sent overseas as the home-based squadrons started to receive the upgraded aircraft which had a top speed of 230 mph thanks to its new 905-hp Bristol Perseus XII engines, although the range, service ceiling and bomb load was the same as the Mk I. Whilst armament was either three or four 0.303-in machine-guns.

During May 1940 four Lysander squadrons were sent to France but as the 'Phoney War' ended and the German attack began one of the squadrons was dispatched to Belgium, however between the 10th and 23rd May eleven were lost both in the air and on the ground. Although there was limited success for the type including a No. 2 Squadron Lysander scoring victories over both a Henschel Hs 126 and Junkers Ju 87 on the 22nd May 1940. With the Allied forces retreating to Dunkirk the Lysander was sent back to the United Kingdom but made a few sorties to drop supplies, however on one such mission only two aircraft out of a total of sixteen Lysanders and Hectors sent returned and in the eight months from the outbreak of war until May one hundred and eighteen of the type were lost along with one hundred and twenty crew members. These heavy losses showed that without air superiority the type of operations that the Lysander was designed for could not be carried out. As a result the Curtiss P-40 Kittyhawk and North American P-51 Mustang started to replace the type.

It looked like the Lysander would suffer the fate of numerous other aircraft and fade out of service in the target tug or air sea rescue role despite the introduction during August 1940 of the Mk III. Powered by either the 870-hp Bristol Mercury XX or XXX engine this would be the slowest Lysander variant with a top speed of 212 mph. It had a range of 600 miles, service ceiling of 21,500 ft and armament of four 0.303-in machine-guns and 500lb bombs. However the Lysander found a new lease of life performing special duties. It would play a vital role with the Special Operations Executive performing clandestine operations in occupied Europe, including inserting and picking up agents behind enemy lines, undertaking its first agent pick up for SOE on the 6th September 1941.

To serve in its new role with the Special Operations Executive the aircraft would undergo a number of modifications including being painted black, as it would now be operating at night, a ladder fixed to the rear cockpit for quicker loading and unloading of passengers, an external fuel tank and rear armament removed. Later on the colours of the Lysander changed to a green and grey camouflage on the top of the aircraft whilst the bottom remained black. Lysanders operating with SOE were designated Mk III (SD) or Mk IIIA (SD).

Mainly used in the reconnaissance role overseas the Lysander also found itself used in the ground-attack role by No. 28 Squadron whilst they were based in Burma, but in March 1942 they were moved back to India and before the year was out were replaced by the Hawker Hurricane as the squadron became a fighter one. The types last action in first line service was in Burma with No. 20 Squadron in late 1943.

The Fleet Air Arm would also use the Lysander, albeit in small numbers, receiving their first of 67 from the Royal Air Force, a Mk IIIA, on the 26th December 1940. In total four FAA squadrons would operate either the Mk III or Mk III TT. During 1944 a number of these had been given back to the RAF.

One of the most unusual Lysanders was the P.12 Wendover which had a Frazer-Nash rear turret installed and a twin tailed tandem wing which was to be used in the event of invasion of the UK, however this never went past the prototype stage.

In total 1,652 aircraft were produced and as well as the Royal Air Force, where it remained in service until 1946, a number of other countries including Canada, France and Portugal used the aircraft.