 In Phase II, a longitudinal study will be conducted to evaluate the effectiveness of a smoking cessation intervention offered by the Department of Psychology, the University of Hong Kong. A total of 600 smokers from corporations will be recruited and interviewed before the intervention at baseline, immediately after the intervention, and at 1-, 4-, 12-, 26- and 52-week post-intervention follow-ups, in an attempt to evaluate their smoking behaviours, knowledge on smoking and satisfaction of the smoking cessation services. Self-reported quitters did not smoke in the past 7 days will be invited to participate in the bio-chemical validation by assessing their exhaled carbon monoxide level and the saliva cotinine level. 