This is a How-to book concerning the application of natural laws in the world of business. The first part of the book, Theory and Practice, presents the theory behind the natural laws considered and illustrates how they can be applied in real-life situations. The second part, Methods and Tools, demonstrates how to proceed in general with a customer engagement from the very beginning. Detail technical advice is given on how to fit S curves and how to employ the Volterra-Lotka equations using EXCEL. All along case studies illustrate the approach describing real engagements. For the science-friendly reader the Appendix includes rigorous mathematical formulations for the natural laws invoked in Part I and for the Excel-based curve-fitting procedures described in Part II.