One of the basic issues in the study of hybrid systems is the well-posednes
s (existence and uniqueness of solutions) problem of discontinuous dynamica
l systems. The paper addresses this problem for a class of piecewise-linear
discontinuous systems under the definition of solutions of Caratheodory, T
he concepts of jump solutions or of sliding modes are not considered here.
In this sense, the problem to be discussed is one of the most basic problem
s in the study of well-posedness for discontinuous dynamical systems. First
, we derive necessary and sufficient renditions for bimodal systems to be w
ell-posed, in terms of an analysis based on lexicographic inequalities and
the smooth continuation property of solutions. Next, its extensions to the
multi-modal case are discussed. As an application to switching control, in
the case that two state feedback gains are switched according to a criterio
n depending on the state, we give a characterization of all admissible stat
e feedback gains for which the closed loop system remains well-posed.