An X-ray photoelectron spectroscopy analysis system for analysing an insulating sample (20), and a method of XPS analysis. The system comprises an X-ray generating means (30) having an exit opening (32) and being arranged to generate primary X-rays (46,56) which pass out of the exit opening in a sample direction towards a sample surface (22) for irradiation thereof. It has been found that the X-ray generating means in use additionally generates unwanted electrons (258) which may pass out of the exit opening substantially in the sample direction and cause undesirable sample charging effects. The system further comprises an electron deflection field generating means (380,480,580) arranged to generate a deflection field upstream of the sample surface. The deflection field is configured to deflect the unwanted electrons away from the sample direction, such that the unwanted electrons are prevented from reaching the sample surface.