Searches for R--Parity Violating Decays of                                     
Sfermions and Gauginos                                                         
via lambda prime and lambda double prime                                       
Couplings at sqrt{s} = 189 GeV at LEP                                          
  
Searches for pair-produced gauginos and sfermions with R-parity                
violating decays via a coupling lambda prime  or lambda double prime           
has been performed using a data sample corresponding to an                     
integrated luminosity of 180 pb^-1 collected with the OPAL detector at LEP     
at a centre-of-mass energy of sqrt{s}= 189 GeV.                                
The searches have been performed under the assumptions                         
that the lightest supersymmetric particle promptly decays                      
and that only one R-parity violating coupling is dominant                      
for each of the decay modes considered.                                        
No excess of such events above Standard Model backgrounds                      
has been observed.                                                             
Limits are presented on the production cross-sections                          
in R-parity violating scenarios and are interpreted                            
in the framework of the Minimal Supersymmetric Standard Model (MSSM)           
as exclusions on sparticle masses and regions in the MSSM parameter space.     
  
 Parallel session :11                  
 Plenary  session :7a