This paper reports the results of a study investigating how accurately programming teachers can judge the level of difficulty of questions in introductory programming examinations. Having compiled a set of 45 questions that had been used in introductory programming exams, we took three measures of difficulty for the questions: the expectations of the person who taught the course and set the exams; the consensus expectations of an independent group of programming teachers; and the actual performance of the students who sat the exams. Good correlations were found between all pairs of the three measures. The conclusion, which is not controversial but needed to be established, is that computing academics do have a fairly good idea of the difficulty of programming exam questions, even for a course that they did not teach. However, the discussion highlights some areas where the relationships show weaknesses.