As part of a larger study aimed at the development of human comfort criteria for the outdoor buikt environment, this longitudinal study recorded behaviour in a number of public areas within a part of downtown Montreal. Observations at intervals included the number of people and their distribution across the space sitting, standing and engaged in some activity. These public spaces have different levels and temporal patterns of use even though they are located close together. Nevertheles, the same threshold conditions for presence seem to apply, in keeping with the theoretical human comfort mode!. That is, sunlighting abd temperature appear to have a preponderant role in observed behaviour. In another part of this study, visitors to one of the public spaces were interviewed and provided assessments of the comfort levels prevailing at the time. The questions to be addressed with regard to the behavioural record are: Do the subjective responses to microclimatic conditions correspond to the obsered levels of use? What part of the variation in use and different behaviours can be explained by setting and what part can be explained by the human comfort model?