Abstract: Health care systems in industrialized countries are built around acute health problems (Etzwiler, 1997). This approach is successful when the goal is to improve or overcome pathologies that result in severe health issues or death. With the recent tremendous improvement of the treatments of life-threatening conditions, the clinical focus has moved from short term results to the overall expected quality of life and long-term outcomes. Unfortunately, the new objectives imply to consider a multitude of interacting processes and variables. In fact, a complex interplay of biological systems (nervous, immune, and endocrine) works together in an integrated and synergistic way to deal with a constantly evolving environment, determining our physical, behavioral, and psychological/subjective conditions. This interplay is the mechanism that allows us to adapt promptly and appropriately to circumstances, the key feature for successful living.