The main objective of this monograph is to develop efficient techniques for tackling the control problems of partially-known dynamical systems. This broad class of systems has a fundamental feature: Knowledge of the dynamic characteristics of the control plant is not complete. In one category, the missing knowledge is due to the unmodeled high-frequency parasitics (adaptive systems). In another category, some of the model parameters are unknown-but-bounded (uncertain systems). The book concentrates on reduced-order adaptive control schemes and deterministic stabilizing control methodologies....