- Social psychology
- Human behavior
- Interpersonal relationships
- Group dynamics
- Organizational behavior
- Consumer behavior
- Advertising
- Media studies
- Communication
- Culture
- Education
- Philosophy
- Science
- Technology
- Society
- The human condition
He has published numerous books, articles, and papers on these topics, and his work has been translated into multiple languages. He is also a frequent speaker at conferences and workshops around the world.