THE MOB CONCEPT IMPLIES THAT PROFESSIONAL CRIMINAL GROUPS OPERATE ACCORDING TO A NUMBER OF COMMON UNDERSTANDINGS, RULES OF CONDUCT, OR WORKING RELATIONSHIPS CONSIDERED BINDING TO THE MEMBERS. AMONG THE 'RULES OF THE MOB' ARE AGREEMENTS THAT GAINS ARE SHARED EQUALLY, THAT THE EXPENSES OF THE MOB COME OFF THE TOP, THAT THE MOB HELPS AN APPREHENDED MEMBER, AND THAT THE MEMBERS DEAL HONESTLY WITH EACH OTHER. INTERVIEWS WITH THE 25 ROBBERS, ALL OF WHOM ARE CONSIDERED TO BE PROFESSIONAL OR CAREER CRIMINALS, AND REVIEWS OF THEIR RECORDS SUGGEST THAT ARMED ROBBERY GROUPS BEAR ONLY SLIGHT RESEMBLANCE TO THE RULE-BOUND MOB. ARMED CAREER ROBBERS DEVELOP A FORM OF SOCIAL ORGANIZATION ESSENTIALLY DISSIMILAR TO THE MOB MODEL AS APPLIED TO PROFESSIONAL THIEVES. THE ARMED ROBBERY PARTNERSHIP IS CHARACTERIZED BY A LOOSE TYPE OF SPECIALIZATION, WHICH IS ADAPTABLE TO CHANGING CIRCUMSTANCES. THE ROBBERY PARTNERSHIP PROTECTS ITSELF AND ASSURES EFFICIENCY THROUGH COORDINATION AND SPECIALIZATION OF THE ROLES OF THE PARTICIPANTS IN THE ROBBERY. BASIC ROBBERY STYLES INCLUDE THE AMBUSH, THE SELECTIVE RAID, AND THE PLANNED OPERATION. PROFESSIONAL ROBBERY SKILLS CENTER PRIMARILY ON PLANNING ABILITY. THE CHOICE OF TARGET IS RELATED TO THE STYLE OF THE ROBBER PARTNERSHIP. CAREER ROBBERS TEND TO CHOOSE COMPONENTS OF CORPORATIONS OR OTHER LARGE ORGANIZATIONS AS TARGETS, AND DO NOT REGARD THE EMPLOYEES WHOM THEY ENCOUNTER IN THE ACT OF ROBBERY AS VICTIMS. THE TYPICAL CAREER ROBBER IS DESCRIBED AS A MAN WHOSE LIFE NEVER MEETS THE STANDARDS OF MIDDLE-CLASS CONVENTION.