P was an air hostess who did the same work but was paid less than male air stewards. EC treaty article 141 demanded that state ensure the “application of the principle that men and women should receive equal pay for equal work.” The terms “equal pay” and “work” were not defined and the article was imprecise. Neither the EC Commission nor the member states considered it precise enough to have direct effect. However the ECJ isolated instances of obvious inequality where the facts were simple, but said that it would not apply to cases where it was necessary to establish complex factual questions, e.g. the “value of work” in jobs of a different nature. The present case was one of clear factual inequality so that in this case direct effect was granted.