Authors and historians have made the words Market-Garden and intelligence failure virtually synonymous. Is this really the case? Operation Market-Garden, the plan envisioned by Field Marshal Montgomery, would open the gate into Germany and simultaneously force General Eisenhower to abandon his broad-front strategy in favor of his narrow-front strategy. Executed on 17 September 1944, this operation became one of the greatest defeats suffered by the Allies during the Second World War. Until 1974, when the British Government declassified Ultra, no one beyond the producers and consumers of Ultra intelligence knew of its existence. With the program now declassified, it was learned that Ultra allowed Allied commanders an unprecedented capability to read high-level German messages that were thought to be unbreakable. The release of these documents now showed that senior Allied commanders knew that the 9th and 10th SS Panzer Divisions were located on the corridor that the Allies planned to make their narrow-front thrust on. Despite this new information, numerous authors still continue to describe as an intelligence failure. While intelligence was not perfect in supporting this operation, it is not justifiable to say that Operation Market-Garden failed due to the intelligence system’s failure to warn commanders of the threat to the operation.