In concentrated marketing, you focus on a narrow market segments (niche markets), rather than the broader market. You only market the product to a group of customers with unique needs. If successful, you can dominate the segment of your choice.
Say, you decide to do clothes business. The next question is whether you will serve all customer segments or not? If you choose to market it only to young women, you are adopting concentrated marketing. Your product is here to satisfy the needs of young women, instead of selling it to all consumers or teenagers (both girls and boys).
In this approach, you can achieve business growth by creating strong loyalty to your product. You also need to build a more intimate long-term relationship with customers.
Concentration marketing requires relatively minimal resources. So, this strategy is suitable if you want to start a small scale business.
Another advantage is that you can also avoid competitive pressures from larger companies. They often do not want to serve niche markets because of the small market size.
However, in the market, you might also have to face many equal competitors. Another disadvantage is that niche markets offer little money because of their limited size and growth prospects.