  In many gauge theories at different values of parameters entering Lagrangian,
the vacuum is dominated by coherent condensates of different mutually non-local
fields (for instance, by condensates of electric or magnetic charges, or by
various dyons). It is argued that the transition between these "dual to each
other" phases proceeds through the intermediate "mixed phase", having
qualitatively different features. The examples considered include: ordinary YM,
N=1 SYM, N=1 SQCD, and broken N=2 SYM and SQCD.
