  The R parity odd renormalizable Yukawa interactions of quarks and leptons
with the scalar superpartners have the ability to violate the baryon and lepton
numbers, change the hadron and lepton flavors and make the lightest
supersymmetric particle unstable. The existence of an approximate R parity
symmetry would thus affect in a deep way the conventional framework of the
Minimal Supersymmetric Standard Model where an exact R parity symmetry is
built-in by assumption. The purpose of the present review is to survey in a
systematic way the direct experimental constraints set on the R parity
violating couplings by the low and intermediate energy physics processes. We
consider first the option of bilinear R parity violation and spontaneously
broken R parity symmetry and proceed next to the trilinear R parity violating
interactions. The discussion aims at surveying the indirect coupling constant
bounds derived from fundamental tests of the Standard Model and the variety of
scattering and rare decay processes. We also discuss the constraints imposed by
the renormalization group scale evolution and the cosmological and
astrophysical phenomenology.
