The present invention provides cytotoxic proteins comprising immunoglobulin-type binding regions for mediating cell-type specific targeting and Shiga toxin effector regions derived from A Subunits of members of the Shiga toxin family for effectuating cytotoxicity. The cytotoxic proteins have uses for selective killing of specific cell types and as therapeutics for the treatment of a variety of diseases, including cancers, immune disorders, and microbial infections.