The construct of alexithymia is most frequently measured by means of the 20-item Toronto Alexithymia Scale (TAS-20). However a number of other instruments have been developed to compensate for problems with measuring alexithymia through self-report measures. Convergence between the different alexithymia measures is rarely studied. This study investigates the convergence among the TAS-20, the Observer Alexithymia Scale (OAS), the Toronto Structured Interview for Alexithymia (TSIA), the modified Beth Israel Hospital Psychosomatic Questionnaire (M-BIQ), and the alexithymia dimensions as judged by the treating psychologist in an inpatient sample (N = 80). Correlations between the total scores were all significant. However exploratory factor analyses of these measures and their subscales indicate that they do not tap into one underlying factor. It is concluded that the TSIA and the M-BIQ are the best indicators of alexithymia, yet a multi-method approach and care in interpreting results are warranted.