- Kabat-Zinn, Jon (1)
- Kafka, Franz (3)
- Kandinsky, Vasily (1)
- Kano, Jigoro (1)
- Kant, Immanuel (5)
- Karr, Alphonse (3)
- Katei, Byron (1)
- Kaufman, Lois L. (1)
- Kavafis, Constantino (1)
- Kay, Alan (1)
- Keen, Sam (1)
- Keller, Hellen (23)
- Kennedy, Edward M. (1)
- Kennedy, John Fitzgerald (9)
- Kennedy, Joseph (1)
- Kennedy, Robert Francis (3)
- Kettering, Charles F (1)
- Key, Alan (1)
- Keyes, Marian (1)
- Khayyam, Omar (1)
- Kierkegaard, Sören Aabye (9)
- King, Billie Jean (1)
- King, Martin Luther (22)
- King, Stephen (2)
- Kingsley, Charles (1)
- Kington, Miles (1)
- Kipling, Rudyard (9)
- Kissinguer, Henry (1)
- Kiyosaki, Robert (1)
- Klapka, Jerome (1)
- Kogel, Joe (1)
- Kolping, Adolfo (1)
- Kondo, Marie (1)
- Koontz, Dean (1)
- Korczak, Janusz (1)
- Korda, Michael (1)
- Krishnamurti, Jiddu (3)
- Kubler, Roland (1)
- Kuenerz, Marly (2)
- Kundera, Milan (4)
- Küppers, Victor (1)
