The primary author of First Things First is Stephen Covey, author of The 7 Habits of Highly Effective People, which I completed earlier in the year. The book is co-authored by husband and wife A. Roger Merrill and Rebecca R. Merrill.
This book does have a lot in common with 7 Habits, but it focuses and elaborates on different points. One focus is on four human needs: to live, to love, to learn, to leave a legacy. Another major focus is how we can use our four special human endowments: self-awareness, creative imagination, conscience, and independent will. Also elaborated on is weekly planning with a "Quadrant II" mentality, that is making sure we make time for the things that are not pressing and urgent, but are important none-the-less.
The four interdependent needs are required for continuing growth. "To live" is about the needs of our body, exercise, eating right and all that. "To love" is about our need for relationships with friends and family. "To learn" is about our need for keeping our mind active. "To leave a legacy" is about our need to connect with a higher power, and the deeper meaning of life.
The four endowments differentiate us as human. Self-awareness is the ability to step back and look at what we're doing. Creative imagination allows us to see many possibilities, other courses of action. Conscience is our connection to the deep principles and truths of this world. Independent will gives us the ability to act on the course of action we choose.
Quadrant II activities are those that are important, but not urgent. Consider preventative maintenance on a vehicle, so that it doesn't break down catastrophically later (requiring important AND urgent repairs). The same concept applies to all our life roles (spouse, parent, employee, etc.). A major aspect of Quadrant II planning is looking at the week ahead a setting aside times for quadrant II activities in each of our roles within that week. As an aside, someone has recreated the weekly planning form described in the book, in the form of a zip'd PDF.
While many of the pieces of this book are similar to those in 7 Habits, they have been put together into a rather different book. This is a worthwhile book, either by itself, or in addition to 7 Habits. Applying even a portion of this material could greatly increase one's effectiveness.