• The role of leaders in the provision of public goods.
  
  
• The motivations of leaders to engage in collective action.
  
  
• Which personal qualities and skills leaders may need.
  
  
• What the "critical mass" is.
  
  
• A "chain reaction" making different people follow leaders.
  
  
• Different degrees of effectiveness achieved by different leaders. Reflect on why some countries and groups have effective leaders, while in others, people accept low-quality leadership.