The investigation of young people lifestyles and attempts to influence them to a desirable direction are high priorities on the research agenda for health and education bodies worldwide, since the formulation of the concept of lifestyle begins during childhood with the dynamic interaction between individual characteristics and the physical environment. Physical activity, diet, participation on passive leisure time pursuits, smoking and alcohol consumption are today important components of the young peoples’ lifestyle. These factors are directly related to the epidemic spread of obesity and a number of physical and psychological disorders. Greeks, of all age-groups, adopted an actually risky lifestyle in these terms of leisure time pursuits. Greek young people spent a great amount of time daily in passive leisure time pursuits and indicate a low interest towards active play and an increase interest for activities of social interaction and sedentary recreation. Furthermore, Greek young people are classified as the most obese between their counterparts of other European countries and they consist the leading group in the adoption of unhealthy behaviours, such as smoking and alcohol consumption. Appropriate intervention programmes are needed. Studies support the notion that interventions must i) target multi-level changes of both individual-level and environmental-level factors in an integrated approach to PA and health promotion, and ii) tailored to the needs, preferences and characteristics of young people. Schools and community can play a decisive role to this direction.