Positive Discipline, by Jane Nelsen
This is the book we used at the high-quality preschool I used to teach at, years ago. I HIGHLY recommend this form of discipline because I’ve seen it work. The main concept in this discipline is RESPECT. Not just children respecting parents, but parents respecting children! Also, check out the Positive Discipline website.
This philosophy uses age-appropriate expectations in a gentle, loving, non-combative way. Excellent read!