Niche markets are defined as smaller subsets of larger mainstream markets.

For example, progressive rock music is a niche market in the larger mainstream
rock music industry.

Some extreme niche market examples could be the eel fishing niche market, the mobile semi-conductor niche market, the twitter lovers niche market, the retro dandy niche market, the elvis imitator niche market and so on....

Niche markets need to be actionable, well-defined yet still have the size to be worth marketing to.

One of the main problems for niche marketing specialists is to find the right markting channels to reach and nurture their respective niche markets.

For instance. There are hundreds of websites, blogs and magazines catering to the mainstream music industry. However,there are only a few niche market media catering to the needs of the neo-punk music niche market.

This niche market issue is also covered in the Long Tail theory of Chris Andersen.

Where 80 percent of all advertising revenue is used to promote and cater to the needs of the mainstream music market (think Britney Spears, Madonna and so on...) - only 20 percent of the shelf space and advertising spend is focused on the niche markets.

Next to that, niche markets are normally very passionate about their niche product.

It's not uncommon that most of the niche market media is self-organised and maintained through volunteers.

This is one of the main reasons mass-media is not an optimal way to reach these niche markets. They simply lack credibility within the niche market.

One good way for a brand to connect with a niche market is to start a co-marketing agreement with a brand that already has credibility within this niche market.

Nike had a difficult time reaching the skater niche market. Nike then struck co-marketing and sponsorship deals with prominent figures within the skater niche market. Amongst other initiatives, Nike and a famous skater would co-design spefic footgear aimed at the skaters niche market. Normally, there is a strong cross-promotion component in these deals. The skater would promote Nike to the niche market, but Nike would also promote the skater to the niche market and beyond.

Some people within the skaters Niche Market would call this selling-out.

Some people within the marketing industry would call this clever cross-promotion to difficult niche markets.