Agencies sell ideas and execution. A client hands over a budget and a problem, and the agency returns campaigns, films, posters, websites, and sometimes a new brand voice. The biggest shops employ thousands of people across planning, creative, media, and production.

The classic structure splits into four functions. Account management faces the client. Strategy and planning figure out what the audience actually needs. Creative writes and designs. Media decides where the money goes.

Common agency types

• Full-service agencies handling everything
• Boutique shops focused on craft or a niche
• Digital agencies built around performance channels
• In-house teams that behave like agencies

Fees come in three main shapes: a retainer, a project fee, or commission on media spend. Retainers reward steady work. Projects suit one-off launches. Commission models have shrunk as clients demand transparency about where their money lands.

Agencies live and die by their pitch record. Win a few big accounts and you hire. Lose them and you shrink fast.