Primary article: Oligopoly An oligopoly is a market structure in which a market or industry is overwhelmed by few firms (oligopolists). Oligopolies can make the motivating force for firms to take part in plot and structure cartels that diminish contest prompting more exorbitant costs for shoppers and less by and large market output.[21] Alternatively, oligopolies can be furiously cutthroat and participate in colorful promoting campaigns. [22]