  Detailed investigations of the structure of hadrons are essential for
understanding how matter is constructed from the quarks and gluons of Quantum
chromodynamics (QCD), and amongst the questions posed to modern hadron physics,
three stand out. What is the rigorous, quantitative mechanism responsible for
confinement? What is the connection between confinement and dynamical chiral
symmetry breaking? And are these phenomena together sufficient to explain the
origin of more than 98% of the mass of the observable universe? Such questions
may only be answered using the full machinery of nonperturbative relativistic
quantum field theory. This contribution provides a perspective on progress
toward answering these key questions. In so doing it will provide an overview
of the contemporary application of Dyson-Schwinger equations in Hadron Physics.
The presentation assumes that the reader is familiar with the concepts and
notation of relativistic quantum mechanics, with the functional integral
formulation of quantum field theory and with regularisation and renormalisation
in its perturbative formulation.
