  The present paper covers the problem of parameters determination for
High-$T_c$ superconductive copper oxides. Different approaches, {\it ab initio}
LDA and LDA+U calculations and Generalized Tight-Binding (GTB) method for
strongly correlated electron systems, are used to calculate hopping and
exchange parameters of the effective singlet-triplet model for $CuO_2$-layer.
The resulting parameters are in remarkably good agreement with each other and
with parameters extracted from experiment. This set of parameters is proposed
for proper quantitative description of physics of hole doped High-$T_c$
cuprates in the framework of effective models.
