The objective of the present study was to develop a scale designed to assess the consequences of working memory deficits in everyday life. The Working Memory Questionnaire (WMQ) is a self-administered scale, addressing three dimensions of working memory: short-term storage, attention, and executive control. The normative sample included 313 healthy participants. The patient group included 69 brain injured patients, who were compared to a subsample of 69 matched healthy controls. The questionnaire was found to have a good internal consistency, both in healthy participants and in patients with brain injury (Cronbach's alpha = .89 and .94, respectively). In healthy participants, significant effects of age (p < .0001) and education (p < .01) were found, due to more complaints in participants aged 60 or more and (unexpectedly) in those aged below 30, and for less educated participants, below high school level. The WMQ was found to have the sensitivity to discriminate patients from matched controls, in the three domains (p < .0001). A good concurrent validity was found with the Cognitive Failure Questionnaire and the Rating Scale of Attentional Behaviour (Spearman's Rho = .90 and .81, respectively, both ps < .0001). In addition, the total complaint score significantly correlated with neuropsychological measures of working memory (visual spans and short-term memory with interference) and with global intellectual efficiency (Raven's Matrices) but not with digit spans. Further studies are needed to measure the internal structure of the scale, and to compare self- and proxy-ratings.