Lots of people rank law firms. And you can dice up law firm rankings in so many ways: by “prestige,” revenues, and more. That’s all great, but if you are going to work in a Biglaw firm, you are going to be working in a specific office. And that office is going to make or break your experience with your firm. Not all offices are created equal, even within the same firm. There are firms that aren’t thought of very highly overall, but a specific office of their operation might be doing great work and be the place for your kind of thing.

With these rankings, Above the Law is trying to capture the strength and relevance of major law firms in today's market. Who are the market leaders? Which firms are still making and retaining their partners? Where do you want to work? But the methods for evaluating the large law firms that are best at the business of practicing law are stuck in the past. The new normal means new challenges for firms. Is bigger always better? More revenue sounds nice, unless the firm is overly reliant on a few rainmakers who can jump ship and leave the rest of the firm scrambling for clients. Surely, the last client who cared about white-shoe status is somewhere trying to find a new ribbon for his typewriter.

The Office 100 blends objective data points (changes in headcount over time, promotional prospects, and number of women partners) with subjective feedback from over 22,000 associates, partners, and other members of the legal community. The result is a more complete picture of each individual office, encompassing employee satisfaction, compensation, reputation, desirability as an employer, and data-driven measures of firm growth. The Office 100 is meant to offer a new perspective on some of the most prestigious and wealthy firms by using a new rubric to show how they stack up both against their competitors and across their own offices.

Over the summer, we conducted the ATL Law Firm Reputation Survey, asking those of you working in Biglaw to rate your peers and competitors. Included in these rankings were market-specific questions, inquiring about both the reputation of firms in each survey participant's city as well as each firm's desirability as a potential employer. In creating the survey, we limited our city-specific firm choices to offices with at least 50 lawyers. Our office rankings include the following markets: Atlanta, Boston, Chicago, Houston, Los Angeles, New York, Philadelphia, San Francisco, Silicon Valley and Washington, DC.

Firms are rated on a scale with 100 possible points:

• Market-specific reputation survey
  “Strength and quality of practice”: 35%
  “Potential employer”: 15%
• Leverage
  Ratio of equity partners to all other attorneys: 5%
• Growth/decay
  % change in headcount since 2010: 5%
• Percentage of women partners: 5%
• Partnership prospects
  % of all non-partners who made partner in the most recent promotion cycle: 5%
• Insider satisfaction
  ATL Insider Survey: 5%
• Compensation rating: 25%*

Clearly, we are making value judgments in choosing and assigning weight to these metrics. For example, we are rewarding firms for maintaining low leverage, or for offering a relatively better chance for incoming associates to eventually ascend to partnership.

Also, to be sure, law firms are not homogenous in their approaches to partnership tracks or compensation structures or other aspects that we have sought to measure here, but we have done our best to account for these differences and create a formula that allows for meaningful comparisons.

The perfect "ATL score" is 100. Each firm is awarded a maximum number of points based on the weight of each metric (a maximum of 25 points for highest compensation rating, 5 points for highest growth headcount, etc.). The points are awarded on a sliding scale from highest to lowest. (For certain categories, firms were placed into tiers and points were apportioned accordingly.) Those points add up to the total ATL score seen on the rankings table.