it was expected that SOE would be the leading partner. In the middle of the war, the relations between SOE and OSS were not often smooth. They established a joint headquarters in Algiers but the officers of the two organisations working there refused to share information with each other. In the Balkans, and Yugoslavia especially, SOE and OSS several times worked at cross-purposes, reflecting their governments' differing (and changing) attitudes to the Partisans and Chetniks. However, in 1944 SOE and OSS successfully pooled their personnel and resources to mount Operation Jedburgh, providing large scale support to the French Resistance following the Normandy landings. SOE had some nominal contact with the Soviet NKVD, but this was limited to a single liaison officer at each other's headquarters. Locations Baker Street After working from temporary offices in Central London, the headquarters of SOE was moved on 31 October 1940 into 64 Baker Street (hence the nickname "the Baker Street Irregulars"). Ultimately, SOE occupied much of the western side of Baker Street. "Baker Street" became the euphemistic way of referring to SOE. The precise nature of the buildings remained concealed; it had no entry in the telephone directories, and correspondence to external bodies bore service addresses; MO1 (SP) (a War Office branch), NID(Q) (Admiralty), AI10 (Air Ministry), or other fictitious bodies or civilian companies. SOE maintained a large number of training, research and development or administrative centres. It was a joke that "SOE" stood for "Stately 'omes of England", after the large number of country houses and estates it requisitioned and used. Production and trials The establishments connected with experimentation and production of equipment were mainly concentrated in and around Hertfordshire and were designated by roman numbers. The main weapons and devices research establishments were The Firs, the home of MD1, formerly MIR(C), near Aylesbury in Buckinghamshire (although this was not formally part of SOE), and Station IX at The Frythe, a country house (and former private hotel) outside Welwyn Garden City where, under the cover name of ISRB (Inter Services Research Bureau), SOE developed radios, weapons, explosive devices and booby traps. Section D originally had a research station at Bletchley Park, which also held the Government Code and Cipher School, until in November 1940 it was decided that it was unwise to conduct codebreaking and explosives experiments on the same site. The establishment moved to Aston House near Stevenage in Hertfordshire and was