Since 1985, Gill has held many different positions in Schlumberger in operational, staff and international roles. Prior to that, she worked for Ford Motor Company.

Amongst her roles in Schlumberger, Gill has been responsible for a worldwide product group in the utilities area, the worldwide Oilfield Services R&D population and more recently has played a key role in setting up and developing a shared services organization for the HR function in Europe, Caspian and Africa. She has been involved in a number of strategic initiatives in the areas of career development, diversity and mobility as well as numerous acquisitions and divestitures. During this time, Gill has spent over ten years in expatriate assignments in France, Germany and the US.

She was appointed to her current role as Director Executive Compensation in November 2005 and is based in London.