During World War II women in the US and the UK were given the then unprecedented opportunity to fly military aircraft. Yet while the women flying in the UK soon gained the privileges and status enjoyed by their male colleagues, the American women pilots were expressly denied the same status, rank, pay, and benefits as USAAF pilots. In fact, after an ugly slander campaign against the women pilots' organisation, the US programme was discontinued and the women were sent home before their job was done. The American women pilots were not less dedicated or inherently less capable than the women flying in Britain. Rather, key environmental and organisational differences and above all a failure of leadership accounts for their fate. This paper summarises the differences and their impact. The complete findings of the comparative research on the experiences of women pilots in the US and the UK during WWII will be published by Pen & Sword Books Inc early in 2006 under the title Sisters in Arms.