We report results of a search for flavor-changing neutral current (FCNC), l
epton flavor, and lepton number violating decays of the D-0 (and its antipa
rticle) into three and four bodies. Using data from Fermilab charm hadropro
duction experiment E791, we examine modes with two leptons (muons or electr
ons) and a rho (0), (K) over bar (*0) or phi vector meson or a nonresonant
pi pi, K pi, or KK pair of pseudoscalar mesons. No evidence for any of thes
e decays is found. Therefore, we present branching-fraction upper limits at
90% confidence level for the 27 decay modes examined(18 new).