| abortion clinics | abrasive products | abrasive products manufacturers |
| accommodation | accountant | accounting |
| accounting general services | accounting services | acting school |
| acupuncture clinic | adhesive manufacturer | adjustment services |
| administration of educational programs | administration of general economic programs | administration of manpower programs |
| administration of public health programs | administration of social programs | administration of transportation |
| adoption attorneys | advertising | advertising-computer |
| advertising-outdoor | advertising-promotional | advertising agencies |
| advertising counselors | advertising specialties | after school |
| after school care | after school programs | ag chemicals |
| ag chemicals manufacturers | agricultural chemicals | air cargo services |
| air compressor | air conditioning | air conditioning supplies |
| air courier service | aircraft | aircraft dealers |
| aircraft equipment parts | aircraft equipment supplies | airline companies |
| airline services | airport | alcoholic beverage |
| ale | alkalies | alley |
| allied products | allied services | aluminum extruded products |
| aluminum extruded products manufacturers | amusement | amusement parks |
| animal clinic | animal fats | animal health |
| animal hospital | animal oils | animal specialty services |
| ankle surgeons | antique jewelry | apartment building operators |
| apparel manufacturer | apparel trimmings | appliance dealers |
| appliances repairing | architects | architectural metalwork |
| architectural services | armored car service | art gallery |
| artists fine arts | art school | asphalt coating |
| asphalt felts | assistants school | athletic goods |
| athletic organizations | attorney | auditing |
| auto cleaning detailing | auto dealers | auto detailing |
| automation equipment | automation equipment manufacturers | automation system |
| automation systems manufacturers | automobile | automobile body |
| automobile body painting | automobile body repairing | automobile dealers |
| automobile detail | automobile detail up service | automobile parking |
| automobile parts manufacturers | automobile parts rebuilt | automobile supplies manufacturers |
| automotive glass replacement shops | automotive repair shop | automotive transmission repair shops |
| automotive trimming | auto polishing | auto supply stores |
| auto transmissions | auto washing polishing |
