Settings and methods - Phase 2 feasibility trial. Two hundred and twenty-four CRC survivors within 12 months of completion of cancer treatment and without evidence of persistent/recurrent disease will be recruited from four public hospitals in Hong Kong after informed consent. Subjects will be randomized in a 2x2 factorial design for the two targeted behaviours prescribed over 12 months. Primary outcome measure is whether the target levels of PA and dietary intake could be met at the end of intervention. Secondary outcome measures include: (1) magnitude of changes in PA level and dietary intakes; (2) rates and determinants of compliance; (3) facilitators and barriers to behavioural change; (4) measurement of theoretical constructs underlying PA and dietary interventions; (5) possible health benefits and side effects (PA-associated injury and nutritional deficiency) arising from the interventions. Outcome will be assessed at baseline, 6 months into intervention and then at 0, 6 and 12 months post-intervention.