In this book, Chapter One discusses the structural properties and phase behavior of neutral and partially charged diblock copolymers in solution. Chapter Two presents a comprehensive study of the complex physico-chemistry associated with the adsorption of polyelectrolyte layers, both single layer or multilayers formed for oppositely charged polyelectrolytes, onto solid surface, paying special attention to the adsorption of polyelectrolytes onto charged surfaces. Chapter Three presents the complexation of the linear, inherently hydrophobic, anionic polyelectrolyte poly[sodium(sulfamate/carboxylate)isoprene] (SCPI) with the cationic surfactant dodecyltrimethylammonium bromide (DTMAB), studied mainly by light scattering methods.