[Authors] A. L. Chistov [Title] Monodromy and irreducibility criteria with algorithmic applications in zero--characteristic [AMS Subj-class] 14Q15 Higher-dimensional varieties [Abstract] Consider a projective algebraic variety $V$ which is the set of all common zeroes of homogeneous polynomials of degrees less than $d$ in $n+1$ variables in zero--characteristic. We suggest an algorithm to decide whether two (or more) given points of $V$ belong to the same irreducible component of $V$. Besides that we show how to construct for each $s