If a law firm were to have 20 equity partners how many lawyer would you expect to work at the firm?

Small firms (under 100 attorneys) typically will have a maximum ratio around 1:1 of other lawyers to equity partners. The larger the firm, the more likely that the ratio will increase maxing out around 3:1 for extremely large firms.

There is NO typical ratio. It isn't even required that all equity partners are still practicing lawyers. In theory, there could be only ONE practicing lawyer. At the other extreme, THOUSANDS of lawyers could work for a firm with only ONE 'partner' although that would not be a partnership.

I worked in firms with partner-to-associate (or "of counsel") ratios of 1:1 (patents, 30 attorneys), 2:1 (corporate and real estate, 90 attorneys) and 3:1 (corporate, patents, and general practice, 200 lawyers).

Some of it depends upon the type of clients and the amount of associate turnover (needing more supervision for noobs).

You might answer that here:

http://www.pwc.com/us/en/law-firms/surveys/assets/...