'Farnborough' was a British series of operations by the Special Operations Executive in German-occupied southern Norway (December 1944/May 1945).

The operations were designed to support the Milorg military resistance organisation by reinforcing its district leaderships and increasing their level of preparedness with special attention to preventing the destruction or damaging of key installations in the event of a German collapse or surrender.

The object of the 'Farnborough I' undertaking was the support of the leadership in the D.11 district covering part of Oslo and the area to the east of it. Parachuted into his operational area on 28 December, J. M. Neerland instructed the district’s most important recruits, the so-called 'Q-teams' which had formed cells and were hiding in the woods. He also examined and adjusted the protective plans that had been produced to cover this area.

One month later, in the 'Farnborough II' undertaking, the same basic task was undertaken in the neighbouring D.12 district, to the north-east of Oslo, by Lieutenant E. Eng and J. Herman Linge, who were parachuted into their operating area on the night 31 December/1 January.

The son of Martin Linge (commander of the 1^st Norwegian Independent Company between its establishment by the SOE in March 1941 and his death in 'Archery' on 27 December 1941), Herman Linge had the additional task of locating and killing Ole Utengen, a Norwegian Nazi, but was captured and eventually transported to Germany.

Meanwhile, Eng began instruction, organised drop zones, and selected those who would have responsibility for protecting key sites. He eventually became chief-of-staff in D.12, working closely with the district leader.

On the same night, 'Farnborough III' saw the arrival by parachute of E. Welle-Strand, K. E. Nordahl, O. Birknes, H. Engebretsen and A. Christiansen as a party to provide the same type of assistance to the Milorg in the D.13 main area of Oslo. This was probably the best-organised Milorg district, which by July 1944 had more than 4,000 men in its ranks. The parachuted party quickly made contact with the leader of the district, which included eight 'Foscott' high-priority targets, nine 'Carmarthen' medium-priority targets and 24 smaller targets. Thus there was a need for considerable preparatory work to ensure that all these sites were protected. Instruction was also undertaken in both tactics and the use of weapons and explosives.

To help in the effort a training a camp was established outside Oslo. On 10 May 1945 all the primary and secondary targets in Oslo were successfully taken over by protection units from D.13.

The night of 29 December saw the arrival of the 'Farnborough V' party (K. Fossen and J. Opåsen) to cover District 14.3, the area around Gjøvik to the north of Oslo. The party quickly established contact with the district leader, but Opåsen was killed in a shooting accident during a training exercise. Nevertheless, over the following months preparations continued for the protection of local targets such as the Raufoss ammunition factory, together with the training of local recruits.

Parachuted into its area on the night of 28/29 December, the 'Farnborough VI' party (H. Stridsklev, G. Bjaali and K. Fjell) covered District 15 on the western side of the Oslofjord, and the 'Farnborough VII' party (J. Irminger and J. Stensnes) covered District 17, most of the county of Telemark in southern Norway. The latter party was delivered by parachute on 1 January 1945 into an area in whose hills the Milorg had formed cells. This is where early training began. Detailed plans were also drawn up for the protection of key sites such as the Hauen transformer station.

The 'Farnborough VIII' party, comprising P. Emblemsvåg, E. Boyesen and J. Elvestad, travelled overland from Stockholm in neutral Sweden to the D.23 district around Lillehammer and the Gudbrandsdalen early in February 1945, and met the Milorg district leader at Tretten. It was instructed to plan protection of important sites in the area and provide local groups with weapons and tactical training. Operating in this area proved difficult, however, especially as the German forces had a major headquarters at Lillehammer. There were several confrontations with German patrols and in one of them Boyesen was killed. Nevertheless, during the early morning of 10 May the Milorg successfully took control of the important sites in the area.

The 'Farnborough X' party, comprising E. Næss and N. Uri, was to cover the D.25 district, centred on Hamar in eastern Norway. The party arrived in Stockholm on 12 February and a few days later travelled to the district and met the district leader, who had already received instructions to organise the protection of selected 'Foscott' targets, which the party was now instructed to assist.

The 'Farnborough IX' party, comprising only O. Berg, was to cover the D.26 district centred on Tynset and Alvdal in the Hedemark area of eastern Norway. Berg arrived by air in Sweden on 19 January and on 14 February reached the district, where he made himself available to the district leader and assisted with preparations for the protection of 'Foscott' high-priority targets.

'Farnborough IV' was to have provided protection the D.14.1 district, Buskerud and Telemark. The undertaking was to have been facilitated by the air delivery of men on 23 February, but the operation was replaced by 'Chacewater'.