During year 2000 the project Optimization of Missile performance has covered three main fields of activities: nonlinear system theory, psuedolinear methods in systems theory and modelling and simulation of a missile at extreme conditions. These three main fields of activities three separate reports. This is the report in the field of nonlinear system theory. Nonlinear system theory has covered the following: o Controlled Lagrangians o Guidance laws/Differential games o Guidance laws/Stochastic differential equations o Differential geometrical integral algorithms The report describes the activities in the fields mentioned above.