Client concentration is the share of revenue that comes from your largest clients. High concentration means a small number of accounts represent a large portion of revenue, creating serious risk: losing one client can threaten the viability of the business.

If your top client is 40% of revenue, you do not have a client, you have a partner who can end your business with one email. Concentration also quietly costs you leverage, because you cannot afford to push back, walk away, or hold your rate. Diversifying is not just risk management, it is how you get your negotiating position back.

Example:

A firm where three clients make up 70% of revenue is one lost account away from a crisis, and negotiates every renewal from a position of fear.

Why is high client concentration dangerous?

Losing a single account can threaten the business. It also removes your leverage, because you cannot afford to lose a client who represents a large share of revenue.

How does concentration relate to acquisition?

It is the clearest argument for building a repeatable acquisition system. Without one, you cannot diversify away from dependence on a handful of accounts.