A reliable and valid questionnaire has been developed to measure the satisfaction of participants with service offered at mammography screening programmes. The questionnaire measures five specific aspects: convenience and accessibility, staffs' interpersonal skills, information transfer between staff and client, physical surroundings and perceived technical competence of staff. A general satisfaction dimension was also included. Systematic procedures were followed to ensure that the initial pool of items met the criteria for satisfactory content validity. These procedures included extensive literature review and interviews with participants and service providers. Discriminant validity was assessed by a modified Q-sort procedure, where eight expert judges sorted items into relevant dimensions. The sample for other validity and reliability testing consisted of 584 women who were participants at a breast X-ray programme in Melbourne, Australia. Concurrent validity was demonstrated by considering the correlation of the sum of the subscale scores for each respondent with their score on the general subscale (r = 0.76; P less than 0.001). Multiple regression was used to provide further evidence for the discriminant validity of the proposed subscales and support for the multidimensional conceptualism of satisfaction. Scores on the general satisfaction subscale were used as an outcome variable and other subscale scores were predictor variables. All subscale scores significantly contributed to the prediction of satisfaction, over and above that of other subscales (R2 = 0.59). This indicates that these subscales are measuring distinct dimensions of satisfaction. Cronbach's alpha of each subscale was over 0.50, indicating that the subscales are reliable. The instrument is a potentially useful tool for assessing the quality of care at mammographic screening services and could be used routinely by such services to monitor satisfaction.