Properties such as inhalation frequency, effort, duration, flow, volume and breath hold are key variables to determine the fate of aerosols from pharmaceutical inhalers, nebulisers and smoking articles. Population lung physiology and function are also diverse. The Smoking Behaviour System (SBS) has been developed to measure flow and duration characteristics of typical smoking cycles, which typically consist of puffing, mouth hold, post puff inhalation, breath hold and exhalation. The SBS is a novel system with regards to its capability to capture the complete smoking cycle. It comprises a head that measures the puffing topography and optical obscuration from puffed particles and a heated second head that measures the respiratory profile and optical obscuration from exhaled particles. The system was calibrated for flow, and validated in terms of system to system and day to day variation for volume and optical obscuration measurements. The puffing and respiratory heads have been tested to operate between flow rates of 0 – 7L.min-1 ( ± 2%), and 0 – 50L.min-1 ( ± 5%) respectively and met this specification on testing. These flow rates are typically encountered during the human smoking cycle. The optical obscuration validation measurements showed no significant difference between units across the five days that they were tested. The results provide confidence in the robustness of the system for use in field studies. These data will be presented and discussed in addition to the characterisation of the complete smoking cycle using the SBS