  In this paper we introduce a unified approach to Toda field theories which
allows us to formulate the classes of $A_n$, $B_n$ and $C_n$ models as unique
models involving an arbitrary continuous parameter $\nu$. For certain values of
$\nu $, the model describes the standard Toda theories. For other values of
$\nu$ it defines a class of models that involve infinitely many fields. These
models interpolate between the various standard Toda field theories. They are
conformally invariant and possess infinitely many conserved higher-spin
currents thus making them candidates for a new set of integrable systems. A
general construction is performed, which can effectively be used for the
derivation of explicit forms of particular higher-spin currents. We also study
the currents in a different representation in which they are linear in the
dynamical variables having, however, a non-linear Poisson bracket algebra. An
explicit formula for this Poisson structure is found.
