( CNN ) The first female engineer to work on offshore oil and gas rigs in the U.K , knows what it 's like to be the only woman in sight for hundreds of kilometers . In her twenties , mathematician Ann Cairns was quite literally thrown in the deep end , working on British Gas rigs in the remote North Sea in the early 1980s . `` It started off with designing pipelines , testing them , blowing up the pipes and seeing what pressure they 'd burst at , '' said the mother-of-one , originally from Newcastle in the north of England . Decades later , Cairns ' office is far more conventional -- though no less demanding . She is now the President of International Markets for credit card giant , Mastercard , overseeing 5,000 employees in over 200 countries . Funnily enough , Cairns says working in investment banking in the 1980s , was a more sexist environment than the all-male rigs . `` I think engineers , as I see it , are really team players , '' she said . `` And providing that you have a scale that people can recognize and you add value to , then you 're seen not for who you are -- but what you can do . '' Towards the end of the decade Cairns was again plunged in the deep end , this time joining Citigroup in 1987 -- just 19 days before the `` Black Monday '' market crash . `` I think if you 're in the engineering world you love fixing things , '' she said of coping under extreme pressure . `` And I found that I thrived in that environment . '' It 's a trait that served Cairns well later in her career -- in 2008 she led the European team managing the Lehman Brothers ' Bankruptcy . Three years later Cairns joined Mastercard as the head of international business , managing all operations for the company outside of the U.S . Does she want to be the ultimate boss one day ? `` I think we have a fantastic CEO in Ajay Banga , but you know I think there 's nothing wrong with being ambitious and wanting to have the next job , '' she said . `` So that 's a 'yes . ' '' `` You 're only as good as your boss thinks you are . And if your boss does n't think you 're great , go and find another boss ! '' `` I hope my daughter has learned that happiness and success are bound together -- you ca n't separate your business life from your family life . '' Insight : Meet the woman controlling India 's money . Watch : Five things you did n't know about Christine Lagarde .
the Lehman Brothers ' boss Cairns was also first female engineer on UK offshore oil rig . Also led the British team managing Mastercard Bankruptcy .