Book of business is common parlance in the United States legal services sector and refers to the collection of clients that a lawyer (usually a partner) has assembled throughout their career.
[citation needed] Firms seeking to expand often retain outside legal recruiters and specify the minimum book of business they require for a lateral candidate, usually between $1–$3 million in larger legal markets.
When a partner resigns from a law firm, American Bar Association and local bar rules require that their clients to be notified, giving them a chance to decide on their own representation.
Given the fierce competition among law firms in the past 20 years, anecdotal reports suggest that partners are informing their clients before handing in their resignations to determine how much of their business is portable.
[citation needed] A conflict of interest check is also an important step before a book of business can be considered portable.