Mark Goldring, chief executive of Oxfam, went undercover to find out what it’s like on the frontline, seeing how the charity’s money is raised and spent, for the Channel 4 programme Undercover Boss.

Disguising himself with a wig and glasses, Goldring spent a week being followed by the television crew as he experienced digging pit latrines in the Phillippines and tried out street fundraising.

The programme description reveals that: “He's surprised to discover flaws in the fundraising operation that could be costing millions, and is shocked that his British staff are fearful for their jobs.”

In a video on Oxfam’s YouTube channel he said: “We have to be open about what we’ve got wrong as well as what we’ve got right.”

Goldring has also written a blog about the experience on Oxfam's website, and says he took part because: “I felt that letting the cameras in to see the reality of Oxfam’s work and our people would help everyone to better understand what we do.”

Oxfam was one of the charities highlighted by The Daily Telegraph in its investigation into executive pay at international aid charities last summer.

He is not the first charity chief executive to take part in the programme – Kim Hamilton, then chief executive of the Blue Cross, went undercover in 2011 and after the programme the charity saw a surge in donations.

The episode will be shown on at 9pm on Tuesday 22 July.